Articles (2020)

Overview

Flashlight progress comes in unpredictable spurts, interspersed with long plateau periods where little notable progress occurs. The first generation of LED lights used several batteries and a current-limiting resistor. The second generation used several batteries and a fairly crude electronic chip to provide current-limiting. The Freedom chip used in the ReX is a third generation device that is somewhat more sophisticated – and it shows.

Slightly larger than their existing Photon line of button-cell flashlights, the ReX differs in three significant respects: its battery is a single rechargeable lithium-ion cell, it has four (instead of the usual one) good white LEDs, and the ReX can be recharged on the go using common inexpensive batteries.

The ReX is fitted with the LRI Freedom controller chip. This chip is reportedly also used in the LRI Photon Freedom Micro single-LED light, but that unit does not have the recharging facility. The battery in the Photon Freedom Micro unit is replaceable, while the battery in the Photon ReX unit is not. The Freedom chip delivers "stepless" variable output and a number of flash modes as well, all operated via the single button. The button is phosphorescent, by the way, making the ReX a little easier to locate in the dark. A spring clip connected to the ReX with a split-ring gives one a way to anchor the little flashlight to hopefully keep from losing it.

The ReX is charged by connecting to a battery (1.2 volt to 3 volt, see below) using a pair of magnet-tipped wires. The wires are anchored to a yoke that connects magnetically to the ReX itself, and the other ends attach to the donor battery terminals. To keep the positive and negative separate, one yoke terminal has a small plastic collar to prevent it from being reversed inadvertently, creating a polarized connector. This is where several of us had some problems: a mismatch in the dimensions of the polarized connector can actually prevent a connection from being made. At the very least, some fiddling is required to seat the yoke correctly and complete the circuit. Proper connection is clearly signaled by a slow flashing from the ReX, which ceases when charging is complete (in approximately two hours with a fresh battery, according to LRI). This is further discussed under the ‘Problems’ section at the end of this review.

The Freedom chip does far more than just control the flashing, however. It is a fairly sophisticated switch mode controller chip, and actually performs four distinct functions:

• Sensing the button to turn the power on and vary the power level
• Converting the four volts from the little cell to a variable mark/space ratio supply to drive the four white LEDs at varying power levels
• Converting the incoming battery voltage to the required voltage to recharge the internal cell
• Monitoring the charging process and turning it off when the cell voltage is high enough

It is, therefore, far more sophisticated than the more common chips found in other LED headlights, which just turn the LEDs on and off at three different brightness levels. This is clearly a third generation device.

LRI claims two full charges from an alkaline AA battery and twenty or so full charges from an alkaline D-cell battery. They champion the use of NiMH rechargeable cells for the least expensive and most environmentally friendly approach (with an average three charges from an AA cell). The ReX onboard Li-ion battery is claimed to have a useful life of three hundred to five hundred charge cycles.

The little charge wire assembly comes with a snap connector that can (and should!) be anchored in some safe place to prevent its loss – it’s hard to envision fashioning temporary connectors from stray or salvaged bits you might have in your pack! The ReX is too small to store the wires on board, unlike the rechargeable Aquastar mUV, for instance.

Interestingly, the ReX isn’t water-resistant, despite not having a battery door. It may be they weren’t able to sufficiently seal the two halves of the clamshell around the four-LED bezel to supply this desirable trait, which is a shame, since the Freedom is splash-proof. However, it seems likely that a few splashes would not do much harm to the unit. The ReX ships with a clip similar to that of the Freedom’s for attaching to a hat, etc. (ReX accessories, including a clip, headband, and solar charger, are promised in the future.)

At the time of writing this review, the LRI website was claiming that "The ReX will charge from any standard battery of six volts or less." This is not strictly correct and should not be followed. Previously, the website was claiming a maximum of three volts, which is correct. The six volt claim relates to charging from a USB connector, but the supply on a USB connector has a protective ten ohm resistor in series, and this reduces the output to under three volts when used to charge the ReX. Our understanding is that a USB charger is planned for the ReX in the future, along with a solar panel.

However, in bench testing, we were sometimes unable to get the charging circuit to start working when the incoming voltage was much above 2.5 volts. The microprocessor is a shade cautious about overload. On the other hand, we found it would work at very low incoming voltages, down to almost 0.6 volts, which approximates a very flat single alkaline cell, which is actually more important.

Operation

A few notes are warranted regarding the ReX modes of operation, especially about how to turn it on. Starting from the off state, a single brief click of the rubber button turns the ReX on to the high setting. Stepless dimming is performed simply enough by pressing and holding the button again. It dims until it reaches the lowest level, which is signaled by a blink. Other flashing modes can then be accessed. Actually, the dimming isn’t really stepless: there are just lots of steps which the eye can’t resolve, except at the lowest power, which is fine.

However, many of us don’t want to start at the brightest setting and kill all our night vision, and this is in fact a common complaint about many LED lights. The ReX has solved this problem: Instead of giving the button a brief press, you can press and hold the button for a moment. The electronics inside senses the longer button press and obliges by turning on at the lowest setting. Holding the button down will then, after a moment, start ramping the brightness upwards. This has got to be one of the biggest improvements in headlamp circuitry for a long while!

If you keep the button pressed beyond the ramp, the ReX eventually enters the signal mode, cycling though slow, medium, and rapid blink modes and an SOS mode. There’s yet another Morse code mode, reached via a series of fast clicks from the off state. In this mode the ReX blinks briefly, once, with each subsequent click. If you don’t know you’re in this mode, the light will drive you nuts until you recall/accidentally discover how to clear it (press and hold).

Most folks most of the time will only have use for the full and stepless dimmer modes, but it’s important to at least learn the others well enough to be able to get rid of them and regain control of the light! One sometimes wishes the marketing guys could be persuaded to skip the frills and concentrate on the basics, despite how nice some of the frills can be at times.

There is an undocumented auto-off point-of-purchase protection mode, but we haven’t found out how to enter this mode in our testing. If you discover this behavior while using your own ReX, then you’ve solved the mystery. You get out of it by pressing the button down for fifteen to twenty seconds. Instructions for this are included with the ReX.

How do they get all these different modes of operation into such a small device? Quite simple really: the central control chip is (we believe) a PIC microprocessor. There’s no part number on it, just the word "REX". All the smarts are in the software. Isn’t technology wonderful?

Basic Performance

The ReX’s bright wide beam is a revelation – how can a flashlight so small do that?!? Fully charged, it’s more like a three- or four-LED headlamp like a Petzl Tikka or Princeton Tec Quad than a button cell light. Without question, this is a light one could hike by – not for hours, mind you, but certainly for a quarter-hour stretch with judicious use. Yes, the little battery inside does have a very finite life when used at high power. More details of this are given below in the technical section.

The beam is the familiar purple-white center with white halo that’s the hallmark of five millimeter white LEDs. The Nichia-brand LEDs have a small shield above and below them, but are more open to the sides, allowing sidespill while controlling top and bottom glare. This configuration makes the beam spill fairly rectangular.

In the Field

The ReX’s four LEDs place demands on the little battery, draining it fairly rapidly on high. Dimmed, it lasts a good while longer, certainly long enough for camp chores and some tent time. If you are making a lot of use of it, you may find it convenient to recharge the ReX overnight, and a single 2,000 mAh NiMH cell should yield two or three full charges. However, if you don’t drain the battery completely each night, many more chargings are possible, and it is hard to give a definite number of possible recharge cycles like this per recharge battery.

The blinking charge indicator makes the ReX easy to find in the dark and makes it very easy to monitor the recharging. Charging on the go is also possible, but the battery, flashlight, and contact wires need to be carefully packed so they don’t disconnect. One won’t know if this happened until unpacking that evening, and our experience is that the connection at the ReX end can be somewhat tenuous.

Rick’s Experiences

I’m used to carrying a technical headlamp and don’t have any misconceptions about the ReX replacing it. For trips where I don’t have to navigate after dark for more than a few minutes, it probably is up to the task. And, because it can always be charged up, it always starts at peak performance, unlike button cell lights with disposable batteries, which generally are partly spent. Also, unlike button cell lights, cost of operation for the ReX is miniscule, especially if you rely on NiMH batteries to charge it. For long trips, lower-capacity eneloop-type cells that hold their charge are preferable to high-capacity but common formula NiMH batteries, which self-discharge rather quickly.

Roger’s Experiences

We recently spent a week in the Australian Alps. This should have been a late summer trip, but the weather decided otherwise, with nights down to -7 C and some rather violent winds. While I normally take some white LED headlamps, I made myself with Energizer lithium e2 batteries, I also decided to take the little ReX on this trip.

Well, what happened was that I mostly used the ReX each evening instead of one of my headlamps. It was just so easy to use in comparison with getting a headlamp out and putting it on my head. I usually needed some light by the end of cooking dinner, so I general hung the ReX from the roof of the tent and turned it on to the lowest power setting while packing up and getting into my sleeping bag.

On another weekend trip down a very narrow and rough rainforest-filled valley in winter time, it was dark by the time I had cooked dinner. Again, I hung the ReX from the roof of the tent, this time so my wife could see to eat her dinner. On one notch up from Low, she found it quite adequate, as the lowest setting was just a bit too dim for ease of use. The photo here was taken by the light of the ReX, although I did turn up the brightness a bit to reduce the exposure time.

I should point out that the lowest power setting really is moderately dim. It was bright enough for getting into my sleeping bag, but if I lost something in the tent I usually had to turn the brightness up at least one notch. (Stepless? Not quite!) It was then bright enough for all my needs, and very seldom have I needed to use it at full power.

For these two trips, I had charged the little rechargeable lithium battery inside the unit fully before leaving. In a calculated gamble, I left the recharging accessory at home each time, figuring that the expected light duty it would get would be within the capacity of the little battery. I was right: the single charge lasted the whole of each trip at generally low power.

Laboratory Testing

For those who might be interested, the ReX may be disassembled fairly easily, and the insides look like this. There is a shell in black, a rubber seal and button cover in white, some electronics on a green PCB with the four LEDS soldered to the edge, and the rechargeable lithium coin cell under the PCB, with a yellow plastic cover.

The Printed Circuit Board (PCB) holds the four white LEDs and the Freedom chip, which is the small integrated circuit (IC) to the right with a blue dot on it. There are also a couple of discrete devices including the essential inductor for the switching operation: the copper coil in the middle. Behind that is the little brass-colored flat push-button assembly in the middle. The red wire at the front goes to one of the metal contacts for recharging. It really looks rather neat and simple.

The steady illumination ranges from high power to low power. It does this by very rapidly switching the bank of four white LEDs on and off. The ratio of on-time to off-time (mark-space ratio) sets the perceived brightness. The ratio is set by a digital counter in the Freedom chip, but the steps are quite small. It is easy to see this as being stepless at anything much above the lowest power. This digital mark/space ratio technique is more efficient than placing a current-limiting resistor in series between the battery and the LEDs.

It should be added here that high power really is very bright and low power really is quite dim: there is a wide dynamic range on this light, much more than on most LED lights.

You can actually see the pulsed illumination if you want to. Turn the ReX on medium to low power on a dark night and wave it rapidly across in front of your face. If you do this correctly, you will see a series of bright white dots in space. Each dot is one of the on-periods. We managed to photograph this, as seen here. Each pulse makes a column of four white dots (the four white LEDs), and there are several passes in front of the camera.

Measurements

Two methods were used to measure the performance of the ReX while switched on and discharging. For one method, Roger’s, the ReX was mounted in front of a photo-sensor inside a dark box, and the output signal from the light sensor was monitored and recorded with a PC-based data logger. For the other method, Rick’s, the ReX was mounted in front of a calibrated Luxmeter (the Lux is a standard unit of brightness) and readings were taken every five minutes. For charging, several parameters were monitored by the PC data logger.

Discharge

For the tests shown here, a fully-charged ReX was turned on and the brightness level was measured over time as the battery decayed. As may be seen in Run 1 of Rick’s results (left hand graph), the light output decayed steadily for a while and then seemed to drop a bit more, around fifteen minutes. The light then decayed away to a low level with a long tail. The second test run (Run 2), gave very similar results. Roger’s results (right hand graph) show a similar behavior, with the decay of the battery voltage also shown.

Clearly the behavior of the ReX changes when the battery voltage gets low: it seems to go into a low-power survival mode. This is very useful. The light level during the survival mode tail might be adequate for settling down in your sleeping bag for the evening.

After one such test, the ReX was given a couple of minutes of off-time while the battery rested and was then turned back on to see what sort of recovery the battery can make. It was found that while there was a little recovery, the effect was hardly worth the effort. Don’t rely on it.

One could say that the battery life of the ReX at high power is not great: only about twenty-five to thirty minutes. You certainly would not want to rely on it for an alpine start up the mountains, for instance. But let’s be realistic: you would hardly expect that sort of performance from something this small anyhow. The unit is so bright that it is tempting to compare it with a headlamp using three AA lithium batteries and a 1 W Cree LED, and that comparison is just not fair! On the other hand, it is surprising just how much power is contained in those little rechargeable lithium button cells.

The discharge test was repeated with the ReX set to its lowest power, and the results were similar – but stretched over a much longer time. For a fully charged ReX, the useful time could be several hours. Certainly there would be plenty of time for cooking dinner, washing up, and getting to bed, and probably for more than one night if you are careful. This is something which would depend very much on how you use the light and how well-charged it was at the start, but it should be possible to rely on the internal battery alone for a three-day trip. That’s an awfully light way to illuminate things.

Recharging – Basics

This is typically done with the little recharging accessory seen in previous pictures. This accessory attaches to both the ReX and an external battery by means of small gold-plated high-power magnets (but see below under the ‘Problems’ section). While recharging, the ReX periodically flashes briefly: if you don’t see the flashes, then the unit is either not connected properly or it has fully charged. The instructions that came with the ReX say the flashing will stop when the internal lithium battery is fully recharged, and yes, this does happen. It may take a while, up to a couple of hours if the internal battery started out flat, but it does work.

The bit which attaches to the ReX unit is physically polarized: one magnet has a little plastic sleeve around it which can only mate with the right contact on the ReX. This is meant to prevent you from attaching the battery back to front. Note that the gold contacts on the ReX are just steel and not magnetic: they won’t prevent you from trying to connect the recharging accessory back to front, but the plastic sleeve should prevent you from making it work. However, be warned: The physical polarization does not stop you from attaching the magnets out at the ends of the wires to the battery the wrong way around (reversed polarity), and while reversed polarity is not fatal for up to fifteen seconds (according to the company), this doesn’t do the ReX any good. A longer period may well do some harm, as the components overheat.

While the company claims you can use a three volt battery, we found that the recharging circuit would often only start to recharge the internal lithium button cell when the applied voltage was under 2.5 volts; three volts was sometimes too high, and the charging unit would not activate. This doesn’t matter if you use a common 1.5 volt battery, of course.

Interestingly, we found that it is also possible to be charging from an external battery while the unit was switched on and giving out light. The company confirmed that this is possible, adding that in this mode the recharging is done with very conservative rules, as the microprocessor is fairly busy looking after the LEDs. Finally, there is another undocumented feature which can sometimes be invoked when the ReX reaches full charge. It gives a very brief flash which signals that the unit is charging, but when really fully charged it can give an intense flash of about one second once every few seconds. This is called the "lighthouse signal," and it is meant to alert you to take the unit off charge. In the meantime, it dumps a bit of excess power every so often. Wonderful what you can do with software!

Recharging – Experiments

For the recharging tests, a bench power supply was set to about two volts and was applied through a current-sensing resistor. The ReX would not start charging with a higher voltage. A number of recharging runs were recorded; some typical results are quoted here. Please note that the length of time taken to recharge the ReX on any occasion will depend on the initial state of discharge and on the power supply used (normally another battery). This means that measured charging times may not be very meaningful. The following will, however, serve to illustrate what happens during a charging cycle.

Here we see a typical charge cycle, starting from a fairly low battery condition. The battery voltage (black) starts to rise as charge is poured in. The charge current (blue) settles quickly to a steady level. Eventually the recharger in the ReX decides the battery is fully charged (about 4.22 volts, in this case) and stops pouring current in. The battery voltage relaxes slightly while the charge current drops to zero. The input voltage (green) rises to the power supply level (in this test set-up) as the voltage drop across the current-sensing resistor drops to zero. The ReX has absorbed about 0.84 watts for about 3,400 seconds, in this case, which seems typical for this unit. However, input power can vary significantly depending on the external voltage source: values from 0.3 watts to 0.9 watts have been encountered, and a wider range may be possible.

Choice of External Battery

The ReX is designed to recharge from an external battery, not from a power supply as used for these measurements. Testing showed that the recharger inside the ReX is able to draw power from an external source down nearly to 0.6 volts. This is below the fully-discharged rating of 0.8 volts quoted for most single cell batteries in the AAA to D range, although the final decline from 0.8 volts to 0.6 volts is usually very swift. This is quite impressive.

For those with a technical mind, it should be noted that the internal impedance of a battery, be it a AA or a D cell, will be far less than the one ohm external resistor used in the tests above. The external resistor was used to allow current monitoring. It also means that you, the user, need to be just a little careful, as a short-circuit across the external battery can be somewhat destructive (to the external battery).

It is relevant to ask what capacity a single-cell battery might have, but this is not an easy question to answer. For instance, the data sheet for the Energizer alkaline e2 AA battery states 2850 mAh to 0.8 volts, but the voltage is falling over the discharge cycle. Assuming a 600 mA load, the AA battery is quoted as providing just over two hours of life. Just how many recharges you might get from one of these batteries is totally dependent on the initial state of discharge of the internal battery. If the internal battery was really flat to start, one might get only a few recharge cycles from such an AA battery.

The data sheet for the standard Energizer alkaline AA battery (not e2) gives significantly lower performance figures at high discharge rates. This battery would seem to provide about half the performance of the Energizer e2 battery. It is not as good a choice for high loads.

The data sheet for the Duracell Ultracell AA alkaline battery uses a different method of presenting performance, so the two brands cannot be directly compared. However, looking at the available data suggests that the performance would be similar to that of the Energizer e2 alkaline AA battery.

The data sheet for the Energizer e2 lithium AA battery is again slightly different. This lithium battery excels at high loads and cold temperatures, and is the one many of us use, despite the higher upfront cost. At a load of 0.9 watts, the battery should be able to provide four hours of life: twice that of the Energizer alkaline e2 cell and the Duracell Ultracell. However, if the power drain is reduced, the life goes even higher. What’s more, this lithium AA battery is half the weight of an alkaline AA.

The ReX literature suggests using a D cell to get twenty-plus full recharges. These D cells are heavier than the AA cells, and we question whether the extra weight is worthwhile for normal walking trips. An Energizer D battery may give up to four or five times as many recharge cycles, but it weighs as many times more than an e2 AA alkaline battery and ten times as much as a lithium e2 AA battery. We would prefer to carry the e2 lithium AA – and they can often be used in cameras as well.

Problems when Recharging and Recovery

Applying the wrong polarity does not immediately damage the ReX, but it can overheat the internal electronics in about ten to fifteen seconds. Failure is certainly possible. Doing so is not a good idea, and it may also flatten the battery. It may also be possible to flatten the internal battery completely just by leaving it on for too long. Once the battery is seriously discharged, the recharging circuit inside may not turn on. This can make it difficult to rescue the ReX from a seriously flat state.

If the battery is only seriously discharged (not damaged), it can be recovered by one of two methods. The first is to allow the lithium battery about an hour or so to recover all by itself. It can sometimes do this, to the point where the recharging circuit will start up again. The second method, which should be used with some caution, requires that you open the plastic case up and apply a carefully controlled and current-limited three volts to the rechargeable cell itself. There are some solder connections on the PCB where this can be done, and doubtless this will void the warranty. Both of these methods have been tested – and worked. (Yeah – some mistakes were made during testing!)

It is also possible (and unfortunately common with the early model units) that the ReX will appear to not accept a charge when you think you have attached it correctly to the recharging accessory and an external battery. The symptom here is quite obvious: it does not flash. Two out of three reviewers, Roger Caffin and Will Rietveld, had this problem. The cause might be a seriously flat battery as above, but more commonly it is due the the polarized connector not making proper contact. In the picture here the gold connector with the red dot is the one described as being polarized. It has a thin plastic shroud around the central gold-plated contact, which otherwise looks like the connector with the green dot.

The problem appears to be that in the early models the plastic sleeve or shroud around the gold connector was effectively a shade too large for the matching hole or depression in the plastic case of the ReX – by a whisker. As a result the gold-plated connectors do not make contact, and there is no circuit. The instructions do say "Do not press or force them into place" and that they will "self-align," but for the early-model units we had, it just didn’t happen that way. Will Rietveld reported having this problem, and the company quickly replaced his unit, in case the problem lay elsewhere. The replacement unit had the same problem, and this persisted until Will tried the "gentle squeeze" described next.

We carefully gave the little accessory part a gentle squeeze onto the ReX body at the appropriate connector. This seemed to push the plastic sleeve on the accessory into its socket on the ReX. When done properly, the circuit was made, and the flashing was visible. We successfully tested this quite a few times. However, Roger found that the repeated squeezing together of the polarized connector had fractured the shroud on one unit. The two pink arrow heads in the photo above point to a pale grey line on the shroud. Viewed under high magnification, this grey line was seen to be a fracture: the plastic had cracked. Mind you, being cracked didn’t mean the unit was unusable.

We discussed this problem with the company. The company attributed the problem to the manual assembly method used for early units: it meant the two halves of the plastic shell were not always properly aligned when the ultrasonic welding was done. They have since moved to an automated system of assembly, which they believe will provide more consistent joining of the parts.

A third problem encountered (by Roger) was that some of the rechargeable batteries seemed to have extremely low capacity, lasting for only a few minutes (about four) at full power rather than the thirty minutes seen in good units. The company reported that some batteries appear to have been shorted out during assembly, and this had severely damaged them (it would!). Again, a replacement unit was quickly provided. In the meantime, Roger spent some time cycling the battery through discharge/recharge cycles, with long float times at the ends. This seems to have restored the faulty battery to better capacity, but with an uncertain life.

Enhancements for the Dedicated Ultralighter

Of course, no dedicated ultralight enthusiast ever misses out on an opportunity to further reduce weight and fine tune his gear. The photo above shows two enhancements which Roger uses.

The red thing on the left is a 200-weight fleece cozy or sleeve, designed to protect the ReX from abrasion inside your pack. It will protect the rubber button and the gold contacts. It’s made from some scraps of generic fleece.

On the right we have the metal clip which came with the ReX. Now having a clip is an excellent idea, of course: it lets you hang the ReX from the roof of your shelter at night. Granted, the clip weighs only about three grams, but it looks so solid (heavy). A suitable UL replacement is shown on the ReX in the middle: a small shaped hook made from 0.9 millimeter stainless steel MIG welding wire. Weight – under one gram. You could probably use part of a paper clip instead – preferably plastic-coated. The hook is folded sideways so that it lies flat against the body of the ReX inside the red sleeve.

Specifications

What’s Good

• Light
• Bright
• Rechargeable
• Reasonable price
• Good company support

What’s Not So Good

• Tricky attachment of the charging accessory (reported to be addressed in the next production run)
• No way to clip to cap (reported to be coming)
• No solar charger (not yet, but a prototype has been seen)
• Not waterproof

Recommendations

• Improve charge wire anchoring or attachment to the ReX itself (priority)
• Integrate a cap clip or provide a minimalist head strap
• Make water-resistant (tricky)
• Provide a truly UL hook

Off the shelf gear is never perfect, unless you’re that mythical “average” size. Even then, there may be features you don’t want and ones missing that you would like. Ideally, all gear would be custom made to exact requirements. Of course, you can make it yourself, and many people do this. For most of us, though, this isn’t an option, especially with complex items like down sleeping bags. Many companies offer options in length and sometimes width, with a variety of features available. But finding a bag the right size with just the features you want, no more or less, can still be difficult. Enter British company PHD and its Design Your Own Sleeping Bag online program. This offers a huge array of options (at least seventeen, depending on the basic style) and is well-designed and easy to use. The bags use the latest, lightest materials and top quality down.

Using this feature, I designed a bag which PHD then made for me. Below, I describe how the process went, what the resulting bag is like, and how it performs. PHD uses metric measurements throughout, and I have followed this. You will need to be familiar with metric weights and measures to use the facility or else have a calculator handy.

PHD

PHD is a small, specialist down sleeping bag and clothing company based in northern England, where all the products are made. PHD stands for Pete Hutchinson Designs. Founder and owner Pete Hutchinson has been involved in producing top quality down gear for mountaineering and polar expeditions, including many to Everest, since the 1960s (he founded the UK company Mountain Equipment in the 1970s). PHD’s standard sleeping bags are excellent – I’ve used several of them in recent years, especially the ultralight +5 C/41 F rated 16 ounce/465 gram Minim and the -5 C/+23 F rated 24 ounce/670 gram Minimus.

Choosing the Route

The process starts on the main PHD web page, where you click on the ‘Design Your Own Sleeping Bag’ box at the top of their home page. This takes you to an intro page with a dramatic snowy mountain scene, accompanied by the sound of a rushing chill-inducing wind and some atmospheric flute music. This only lasts seconds but can be skipped. This leads into the opening page, which tells you that there are two design routes, a free route for the experienced, who have used sleeping bags and understand their design, and a guided route for those who need assistance.

The Guided Route

Select the Guided Route and a page opens to enter the minimum temperature you expect to the bag to handle. This brings up a selection of PHD bags close to that rating. Change the temperature and the selection changes. The weight and price of the bags are given, along with their categorization as ultralight, which means few features, or hi-tech, which means many features. Continuing in the Guided Route allows you to modify these standard designs. Click on one of the bags and a page comes up with information and details. Click on ‘Choose This Bag’ and the actual design page appears with all the options. These also appear in the Free Route and are described below. In the case of the Minim 400 sleeping bag I chose for this example, after entering -5 C, I added some features which raised the weight and price. It is always possible to go back and change your design if it’s not working out as you wish, and you should review the design before submitting an order.

The Free Route

The Free Route is the one to choose if you know the type of bag you want and don’t want to be restricted to modifying an existing PHD bag. The first decision to be made is whether you want a lightweight style or hi-tech style bag. Full details of each are provided. The lightweight style is a simple design with an open hood (which means a zipper isn’t essential) and box wall baffles. The high-tech style has trapezoidal baffles, vertical channels over the chest, side channels and a close-fitting mummy hood that doesn’t open wide. PHD says hi-tech bags are for extreme expedition use and high altitudes. For most backpackers the extra weight of a high-tech bag is probably not justified. I certainly wanted the lightest bag possible for the minimum temperature rating and so chose the lightweight option. As an exercise, I also designed a hi-tech bag with the same fill and shell fabrics as the lightweight bag described below. It weighed 364 grams more and cost £83 more, both substantial increases, but the minimum rating was the same.

Once a choice has been made between lightweight and hi-tech, the next decision is the amount and quality of the down. The possible quantity of down runs from 200 to 1300 grams in 50 gram increments and 700, 800 and 900 fill power down is available. If you’re not sure what the differences between these are, or how much down you need, you can click on ‘view important information about this option,’ and a pop-up chart appears showing you the temperature ratings for different quantities and qualities of down. Bags can be designed with minimum temperature ratings from +7 C/45 F to an astonishingly cold -64 C/-83 F. Sensible warnings point out that this is only a rough guide and that many factors need to be taken into account, both subjective (metabolism, tiredness, food and drink) and objective (humidity, wind, sleeping pad, clothing, altitude). I wanted a bag that would keep me warm down to around -5 C. The 400 grams of 800 fill power down had this rating but the same amount of 900 fill power down had a -8 C rating. That little extra touch of warmth with no increase in weight sounded appealing, so I chose the 900. No choice is fixed however; you can always change it later on in light of the weight, cost, or temperature rating of the bag.

Once the quantity and quality of the down has been chosen, you move onto choosing the details. The next page shows the basic bag with the price, weight, and temperature rating. Each time you make a decision that affects any of these, they change so you can keep a precise track of them and go back if necessary. There are seventeen different options covering outer and inner fabrics, color, stuff pattern, zippers, hood, down fill power and weight, down overfill, collar, inner panels, side baffles, hood and collar cords, bivvy cowl, length, and width. With all these options, there are explanations and definitions to help with your decisions. The number of permutations is enormous and fun can be had changing them and watching how the weight, temperature rating, and price change. Here’s a rundown of the options, their usefulness, which ones I chose, and why.

Fabrics

Four shell fabrics are available. M1 is a microfiber weighing 42 grams per square meter (g/m²). MX is an ultralight ripstop nylon weighing 30 g/m². Both are highly breathable, downproof, wind resistant, and fast drying. Drishell is 48 g/m² ripstop nylon with an ultralight coating. The seams aren’t waterproof, but the fabric is water resistant, and it’s still very breathable. The fourth choice is 70 g/m² Gore-Tex with fully taped seams. This shell is fully waterproof and lowers the bag’s minimum temperature rating to -13 C, but it also adds considerable weight, (the bag weighing 870 grams as opposed to 640 grams for one with an MX shell) and price (£381 as opposed to £259 for the MX). The Drishell outer would be a good choice for use with tarps in damp climates. The Gore-Tex shell might be useful on polar expeditions or alpine climbing, but is too heavy for backpacking, in my opinion.

I prefer highly breathable ultralight sleeping bag shells so the down can loft fully and body moisture can escape quickly, so I chose the MX shell, as it’s the lightest. I rely on my shelter, whether bivvy bag, tarp, or tent, to keep off rain.

The choices for inner fabric are MI, MX, Drishell, and 54 g/m² Pertex, which is the least expensive, but also the heaviest fabric. Again I chose MX.

Color

The choice in colors is not great. Drishell has most with four – red, black, blue, and gold. For M1 and Gore-Tex, the choice is red or black. For MX and Pertex it’s the old Henry Ford choice – black, black, or black. Luckily, I like black for sleeping bags, as it absorbs heat and dries fast when aired in the sun.

Stuff Pattern

This is an interesting option that allows you to have the down redistributed so there is more on the top, base, or foot of the bag. In a standard PHD bag, the down is distributed almost equally, with just marginally more over the chest and at the foot. Obviously if you have more down in one area there will be less everywhere else, reducing the overall warmth of the bag (PHD doesn’t say how much down is redistributed). However, if you suffer from cold feet (a common complaint) or a cold chest, then having more down in the foot or on top could be useful. If choosing this option, I would start with a bag rated for colder temperatures than I expected so that even with less down in some areas it should still be warm enough. However, as I don’t generally feel particularly cold in any one area, I chose the standard stuff pattern.

Zipper

Zips can be on the right or left side, long or short, with single or double draft tubes. I was interested to see just how much weight a zip and draft tube adds – 150 grams for full length zip with double draft tube, 120 grams for full length zip with single draft tube, 65 grams for short zip with double draft tube and 55 grams for short zip with single draft tube. I avoided any extra weight by opting for no zip at all. This reduces ventilation options, but that’s not something I’ve ever found to be a big problem.

Hood

The choice is between an open hood, which can be tightened around the head when needed but which allows good ventilation when fully open, and a mummy hood, which always fits close round the face. The bag has to have a zip to have a mummy hood, so I’d have had to go back and choose a zip if I wanted one. I prefer an open hood anyway, as it’s more versatile.

Down Overfill

After confirming or changing the amount and quality of the down, there’s an option for putting extra down into the shell so the down is packed more tightly. PHD points out that they optimize the amount of fill and the shell size, and that an overfilled shell doesn’t have as good a warmth to weight ratio, but some people like a thicker feeling bag, and it reduces the chance of thin areas appearing due to the down shifting as you move in the bag. A better warmth to weight ratio can be had by increasing the standard amount of down in the previous step or the quality if 700 or 800 fill power down has been chosen. The amount of down overfill is 100 grams. If chosen this would have lowered the minimum temperature rating of my bag from -8 C to -11 C. However, if I’d increased the amount of down by 100 grams and had a shell sized to go with this, the rating would have been -14 C at a weight increase of 15 grams over the overfilled bag.

Collar

This is a simple option: to have a collar or not. I chose not, as one adds 60 grams of weight, and I don’t like collars much anyway, as they restrict ventilation and don’t seem to make much difference in warmth.

Inner Panels

Water resistant panels in the hood and the foot can protect the down against moisture from your breath or dampness from socks. I’ve used bags with these, and they do work, especially the one in the hood. I haven’t had serious problems without them however. PHD’s Drishell panels only added 10 grams (and £15 in cost) so it was tempting to add them. However I wanted the lightest bag for the warmth, so I resisted.

Side Baffles

Side baffles prevent the down from shifting from top to bottom and vice versa. In bags without them, you can shift down from one side to the other to increase or decrease the warmth. If, that is, you can keep that side on top. Those who turn in their sleep and often wake with the bottom of the bag on top, as I do, learn that no side baffles can mean waking in the early hours with a cold back as the down has shifted. That is my one complaint with PHD’s off the shelf ultralight bags – they don’t have side baffles – and a main reason why this design option is of value to me. So I chose the side baffles, despite the 10 gram weight increase – my only concession to a feature that added weight.

Hood and Collar Cords

The choice here is between stretch and non-stretch. Having used both, I find non-stretch hood cords easier to use and less likely to allow the hood to gape, letting in cold air. If I’d chosen a collar, I’d have gone for a stretch cord, as these give when you move, making them less restrictive than collars with non-stretch cords.

Bivvy Cowl

This is a curious option that is basically the top half of a bivvy bag. It’s made from proofed nylon and lies under the bag when not needed. Pulled up it covers the head and body down to the chest. There’s an elastic drawcord in the hem but no zip. The seams aren’t sealed, so it’s not fully waterproof. PHD says it’s for below freezing conditions, not rain. In combination with a bag with a waterproof shell, I guess you could sit out a blizzard on a ledge during a climb with this, but I don’t think it’s of great interest for backpacking. It adds 100 grams to the weight and £37 to the cost.

Length and Width

Being able to choose from five lengths and four widths is one of the great benefits of PHD’s Design Your Own Bag, as many people find the choices in off the shelf bags too limited and end up with bags that are too long, too short, too wide or too narrow. In lightweight bags, PHD offers lengths for people up to 142 centimeters/62 inches (X-Short), 168 centimeters/66 inches (Short), 183 centimeters/72 inches (Standard), 198 centimeters/78 inches (Long) and 213 centimeters/84 inches (X-Long). Being 5’8″, I chose the Standard length. The widths refer to the maximum torso circumference, whether the chest or waist. The options are up to 92 centimeters/36 inches (Slim), 109 centimeters/43 inches (Standard), 121 centimeters/48 inches (Wide) and 135 centimeters/53 inches (X-Wide). Again, I chose the Standard width. (For some reason, PHD gives English and metric measurements here).

The Final Decision

Once all the decisions have been made and perhaps considered and reconsidered, you can review the bag you have designed and submit your order. Before doing this, you can save a copy of your design and email it to yourself as well. This is done by clicking on the floppy disc image in the lower left corner of the sleeping bag picture. This saves the design and brings up a box in which you can enter your email address and then click to have the design emailed to you. I did this and a few minutes later received an email containing the following:

Your Bag Design

Delivery

PHD gives deliver time as twenty-one days in the UK, thirty days outside the UK. Mailing charges are £15 for the UK and the EU and £25 for other countries. My bag arrived in a week, but it was a special order for this article.

The Sleeping Bag

Of course, for the application to be really useful, the end product – the sleeping bag itself – has to fit the design brief. The bag supplied does this perfectly. The dimensions are correct and the weight is 652 grams/23 ounces. The fit is on the slim side, but there is enough room for me to move in the bag and to wear clothing if necessary. The MX fabric is very soft and comfortable, and the bag feels luxurious to sleep in.

The bag is supplied with a stuffsack weighing 25 grams/0.88 ounces and a big mesh storage bag. The stuffsack measures 30.5 centimeters/12 inches by 18 centimeters/7 inches, which is quite compact for a bag with this rating. It can be compressed to half this size. The stuffsack isn’t waterproof, so in wet weather, it will need to be stored in a waterproof pack liner or replaced with a waterproof stuffsack (or both if you want to be really certain it’ll stay dry in the pack).

I haven’t yet been able to sleep in the bag at -8 C/17.6 F, as early autumn temperatures in Scotland do not often dip below freezing. At +5 C/41 F, I was very warm with the hood wide open.

Comparable with the PHD bag is Rab’s Quantum 400, one of my favorite bags, which weighs 885 grams/31.2 ounces and costs £250. The Quantum 400 has 400 grams/14.1 ounces of 750 fill power down (European measurement)/850 fill power down (American measurement), and is rated to -5 C/23 F. PHD uses the European fill power measurement. However despite the theoretically higher lofting down in the PHD, I measured the loft of both bags as 13 centimeters/5 inches at the chest. The Quantum 400 has a full length zip with a baffle and a collar. If I’d chosen these features for the PHD bag, it would have weighed 830 grams/29.3 ounces and cost £304, still lower in weight but significantly more expensive. The Quantum 400 is slightly longer than the PHD at 215 centimeters/84.6 inches as opposed to 210 centimeters/82.7 inches. The Quantum 400 has kept me warm at -7 C/19.4 F, so I expect the PHD bag to do the same.

The Process Summed Up

The Design Your Own Bag application is easy, quick, and fun to use. All the options are clearly explained, as are the relationships between them when necessary (such as having to have a zipper with a mummy hood). Being able to see how changes affect the weight, temperature rating, and price of the bag, plus the choices you have made, means you are always fully in control of the process and can change any option at any point. This is a very well-designed program. Of course there are many good off the shelf sleeping bags, including those from PHD, and most people find one of these fine. However Design Your Bag provides the opportunity for a customized bag that is exactly what you want and which can solve problems of size for those who don’t fit off the shelf bags. I think it’s excellent.

For winter 2009, Patagonia has released a new lineup of lightweight softshell clothing targeted at climbers and high-output mountain travelers (that’s us, folks). The Traverse product line includes a jacket, a pullover, and pants. The jacket and pants are available in both men’s and women’s styles, while the pullover is only available in men’s style. The specified weight of the men’s jacket is 9.9 ounces (women’s is 9.0 ounces), and its measured weight on our scales is 10.2 ounces. The pullover weighs in at the specified 9.2 ounces, and the pants come in at 8.8 ounces (both for size M). The women’s pant is slightly lighter at 8.6 ounces.

The fabric for all the Traverse series products is a 4.7-ounce-per-square-yard, 70 denier, 93% polyester, 7% spandex with four-way mechanical stretch and DWR finish. The jacket has a full zipper, two handwarmer pockets, and a bicep pocket. The pullover has a half zip and a single chest pocket with horizontal zipper. Both the pullover and jacket have elastic cuffs and a slight drop tail. The Pants feature an elastic and drawcord waistband, two zippered handwarmer pockets, gusseted crotch, and straight leg cut. All garments are cut with a slim fit.

We’ve had the jacket and pants over the past few months for an early look. My jacket has accompanied me on winter trail runs, many training hikes, and a few trips in my local mountains. The fabric is indeed quite stretchy, perfect for use on climbs and strenuous off-trail hikes. I had the jacket out in several nasty windstorms, and it seemed very wind resistant, but I would not say it is windproof (and it is not intended to be). During aerobic activity, it performed quite well as wind protection. Breathability in heavy aerobic use was very good – much better than a wind shell such as a Patagonia Houdini. This shell is perfect for cold weather training, or strenuous fall and winter hikes. I did find myself opening the zipper for extra ventilation on strenuous climbs with temperatures in the low 50s.

In minor rain, the DWR treatment did fine, but I wouldn’t expect these garments to hold off rain for long periods of time. Build quality and workmanship is superb, with good stitching, high quality (but heavy) zippers, and nice touches such as a mesh-lined stand-up collar. Durability was good during my testing, but I did not take the jacket through any long, rocky climbs. I did have it on several bushwhacking sections that stressed the fabric, and it came through with no snags or pulls. I found the slim fit and stretch fabric to be functional for the intended use in high output activities. The handwarmer pockets in the jacket were cut too low for use with a hip belt, but were useful during cool rests. Note that the Pullover does not have handwarmer pockets – just a single chest pocket.

Ryan Jordan tested the Traverse pants over the spring and summer, and found them to be a comfortable, fast drying pant. At 8.8 ounces, they are lighter than most other comparable pants and the stretch fabric makes them very useful in technical hiking and climbing. Ryan found that the pocket design limited the usefulness of this garment as a trekking pant, as the two pockets are shallow and difficult to use for typical trekking storage (compass, small camera, etc). Ryan also found the black fabric on the pants to be limiting in warm or hot weather.

While not a product that would be targeted at an ultralight three-season kit, the Traverse garments are a good option for cold weather, or for summer alpine conditions. The pants are lighter than most other summer pant options. The jacket and pullover are better suited to cooler conditions. My jacket is my new favorite for winter training.

The Traverse Series will be available in January 2009.

Specifications

Overview

The Komperdell Nature Stick Carbon trekking poles are based on the highly rated Komperdell Carbon Featherlight trekking poles (which are nearly identical to the Backpacking Light STIX carbon fiber trekking poles). A similar tapered carbon fiber shaft is used, as is a similarly-sized and shaped grip. However, the look is totally different.

Unlike the Carbon Featherlight, the Nature Stick Carbon hides its carbon fiber beneath a natural bamboo overlay that is strikingly beautiful. It is a work of art, showing no seams or imperfections. Despite many months of hard usage through cold winter snowshoe trips and mid-summer downpours, the bamboo has proven quite durable, and I’ve experienced no lamination or warping issues of any kind. The graphics on the shafts are minimal and tasteful, highlighting the bamboo’s natural beauty.

Also unique to the Nature Stick Carbon are the leather grips and straps. The shape of the grips is very similar to other Komperdell grips – comfortable and usable for a wide range of hand sizes. The leather is soft and durable and remained somewhat tacky when wet, eliminating any slippage concerns. The leather seams are highlighted by large stitching and the leather straps have a grey embroidered logo – classy.

Besides being gorgeous poles, the Komperdell Nature Stick Carbon poles are serious performers. The oversized carbon/bamboo shafts taper from 17 to 11 centimeters and are both stiff and effective at damping vibration. These poles flex only during very hard landings, making them a great choice for hikers who carry heavier packs, or need a longer pole length.

Using our new 2008 Backpacking Light Pole Stiffness Test, the Komperdell Nature Stick Carbon poles were supported in a fixed rig at a 100-centimeter length, with a 25-pound load suspended from the center of one pole. Pole deflection was then measured using calipers. The Nature Stick Carbon poles deflected just 2.7 centimeters, nearly identical to the Komperdell Carbon Featherlight and Backpacking Light STIX poles.

While not the lightest poles on the market, the Nature Stick Carbon poles weigh just 5.3 ounces in a 125-centimeter length. This is just 0.5 ounces more than the comparable Komperdell Carbon Featherlight and Backpacking Light STIX poles. The tapered shafts lighten the poles near the tips, lowering swing weight and making quick placements easy.

One downside of the Nature Stick Carbon poles are the tungsten/carbide tips. While the tips work fine, they only accept Komperdell-specific press-fit baskets (Black Diamond press-fit baskets are too small and won’t fit). Further, once the included baskets are installed, they are very difficult to remove. I wish these poles had come with standard Komperdell tips that accept the more common and more versatile Komperdell twist-on baskets.

If you are looking for a modern trekking pole with a classic look, the Komperdell Nature Stick Carbon poles are a fantastic choice. At approximately $142, they are expensive, but still in the ballpark of comparable carbon fiber poles. That said, tracking down a pair may prove quite difficult – you’ll need to direct your browser to a handful of sites in Germany or Russia to find them. What you’ll end up with, though, is a truly unique and beautiful set of poles that you aren’t likely to see on the trail again.

Specifications

Technical Background

To be legally called a ‘purifier,’ a unit has to meet the EPA specifications for blocking the passage of protozoa (large), bacteria (medium), and viruses (small). The industry term ‘microfilter’ does not have a legal definition, but is generally taken to mean a filter which meets the EPA specifications for bacteria and protozoa, but not the specifications for viruses. In general, viruses are just too small for small filters.

Most microfilters use either a labyrinth filter (a maze of twisty little passages, all the same) or an absolute filter layer (holes no larger than the filter rating). The latter may be referred to as a membrane. Both sorts have the disadvantage that they block up fairly quickly when handling murky water, and you have to either mechanically scrape the filter cartridge surface clean or replace the cartridge.

This MSR Hyperflow filter is a little different. Instead of having a single cylindrical membrane, it has a mass of fine ‘micro-porous’ tubes all bundled together. The tubes have tiny 0.2 micron holes in the walls for the water to flow through: holes small enough to block the bugs. Water is pumped from the outside of the tubes into them, to emerge at the open end. MSR calls this a ‘Hollow Fiber Membrane’.

The photo above shows the ends of the little tubes. They look as though they are packed very loosely in the block of epoxy at this end, but this is a bit deceptive. The tubes do not go down to the other end of the cartridge and stop there: instead they are actually folded over at the bottom so that both ends are at the top face shown here. If you peer inside the other end of the filter cartridge, you can just see the fold of the tubes.

The filter cartridge seems fairly robust, although MSR cautions against dropping the cartridge by itself onto hard surfaces. If it is dropped, it can be tested by the user: instructions are included for this. MSR also cautions against letting the wet cartridge freeze. Ice is likely to rupture the fine tubes, so this unit is not suitable for winter trips.

So far, this filter unit has strong similarities to other membrane filter cartridge units. But this MSR Hyperflow cartridge can be ‘back-flushed’ with clean water. The idea is that back-flushing causes most of the stuff sitting on the surface of the tubes – dirt, algae and bugs, to be dislodged from the surface. This should leave a clean surface and restore the filter to nearly full capacity. You can also disinfect the filter with a very dilute solution of household bleach for storage.

For those curious about the details of the mechanism, it seems that when the filter is back-flushed, the pressure inside the tubes increases, which forces them open just enough that particles wedged in the very small holes should fall back out of them and go back out the inlet port of the filter. Of course, you must use clean (filtered) water to do this!

Product Details

The filter package consists of the filter itself, an outlet adapter for the standard Nalge bottle thread, a long silicone rubber hose and a float to go on the end of the hose. There’s the inevitable stuff sack, of course, with a sewn-in set of instructions about how to arrange the valves. Finally there’s a wrapped bundle of instruction leaflets in a huge range of languages.

MSR claims that the Hyperflow weighs 209 grams (7.4 ounces), but the full kit is much heavier than that: over 300 grams (10.6 ounces). I was able to get a ‘minimal’ kit down to about 220 grams (7.8 ounces), although the exact weight varies depending on how much water is left inside.

The inlet filter is a neat idea. Instead of a small bobble or acorn which floats underwater, this filter floats face down on the top of the water. This gives it a largish surface area and also lets you get water from very shallow sources. Rub the filter face into the mud, and it will block up, of course, but it’s actually a fairly tough nylon mesh which can be easily back-flushed to clear muck off the surface.

The silicone rubber tube can be detached from the inlet filter, so the latter can be replaced. The hook and loop tapes attached to the inlet filter are meant to allow you to bundle the whole thing up neatly, but they seemed to be more of a hindrance than anything else, really. They thread through slots and can be disconnected very easily, too. After a very small amount of use, the tapes were removed from the field test package and the weight quoted below is without them.

The Nalge-compatible cap or connector looks neat, but it has several deficiencies. For a start, at 37 grams (1.3 ounces) it seems a bit like excess weight. In addition, having the filter connected this way to the bottle turns out to be very inconvenient during filtering for a couple of reasons, which will be explained later. Finally, the connection between the pump and the cap is not watertight, so when you tip the Nalge bottle upside for back-flushing, water dribbles out everywhere.

One alternative to the cap idea is use a second bit of silicone hose to go from the outlet to whatever water bottle you are using. There is a far more useful spigot in the middle of the outlet fitting which will conveniently take such a silicone rubber hose. If you don’t have some spare silicone tubing handy, you could even cut off about 200 – 300 millimeters (8 – 12 inches) of the long inlet hose and use that. You would need to keep this outlet hose clean, of course: it could, for instance, be carried in a very small ziplock bag. It would be nice if MSR could also provide a ‘hook’ to make the hose hang on the neck of any bottle, like the one which comes with the Katadyn Hiker, shown above.

MSR claims that the outlet fitting will fit into ‘most water bottles’. It may fit in some, but it is just too big to fit into the neck of the 1.25 liter fizzy water PET bottles I use all the time. However, I don’t think this matters, as the whole idea of a direct connection turns out to have relatively little practical value.

Product Operation

Basically, you put the inlet filter in the water source and pump. The filter has a pump action which – when new, is a bit softer than some other models we have tested over the years. The action needs to be soft if it is to be pumped between one’s arms as shown here, but you can hold it in other ways of course. The flow rate is quite good – when new, for all the low force involved, and this is due to the rather large surface area of the filter – all those little tubes of course. MSR claims one liter every 20 strokes, or ‘more than 3 liters per minute’. My maths says that means they expect you to do 60 pumps per minute, or one pump per second. Hum – that might be a slight exaggeration of my arm strength, especially at the end of a hard day. More on this later.

Sooner or later the filter will block, and it’s then time to strip it down for back-flushing. What this means is that you have to reverse two small valves, one on each end of the pump. One is at the middle of the filter and one is inside the inlet housing. You unscrew the lower part of the pump to reveal one of the valves, as shown below. You take the valve out, reverse it, and pop it back in. Then you repeat this at the inlet end, inside the black lump. That valve is slightly larger and can be extracted using two long bits sticking out from the face of the valve. The instructions are clear about how to do this.

Then you feed clean water into the outlet end and pump to ‘back-flush’ a bit. The accumulated muck should then fall out. The main instruction booklet covers the back-flushing process quite well. In addition, there is a second instruction leaflet which includes detailed instructions on an easily-done test the user can perform to confirm that the filter remains intact. This attention to easy field maintenance and user confidence is gratifying.

Formal Laboratory Tests Results

We requested information from MSR about laboratory test reports to demonstrate compliance with the EPA specifications. The MSR reply was as follows. We feel that MSR’s reputation is good enough for this to be an acceptable assurance at this stage.

"As for the test reports, I don’t have anything available to give you at this time. We are in compliance with the EPA Guide Standard for the removal of bacteria and protozoa. We have tested the filters rigorously in-house, meeting a variety of internal performance specifications as well as the NSF P231 standard for the removal of bacteria and protozoa. We will have test reports available on the website soon, but I do not have a timeframe. For this I apologize, but we’ll have it available as soon as possible."

Initial Assessment

Well, of course, the first thing I did was to try to access the valves and the end of the filter. I tried… and failed. I simply could not get the pump to unscrew. This prompted some emails with MSR, who responded very quickly. To cut a long story short, I was testing a manually assembled pre-production unit which had somehow acquired one O-ring too many. The excess O-ring was blocking the mechanism needed for unscrewing the pump – but I didn’t know that at first.

MSR sent a replacement unit without question. Once I had pulled that one apart I could see where the problem was, and was able to disassemble the first unit and extract the errant O-ring. I sent a photo to MSR, and they were quite surprised. But they were prompt to reply to all my requests for assistance. So Backpacking Light ended up with two functioning units for testing. This allowed the testing to be done by two separate Editors.

The first brief test was conducted using water from the dam on my farm. The dam has ducks swimming in it, and sometimes looks a bit murky. Typically I can see a few feet down through the water, but not much more. We use this water for all our family needs, except drinking water, at home. It is pumped up from the dam through a neat Israeli filter which we clean out once every couple of months. There is some suspended algae, but not a huge amount.

You might say that I should be testing the unit with better water than that, but this is not so. If I am high in the mountains and collecting water from a little stream, I usually don’t bother to filter it. It is when I have to get water from a source like the dam that I want to use the filter. (We use this water for everything in my house except drinking: we have a rainwater tank for that.)

The filtered water is on the right, while the unfiltered water is on the left. The plastic in the front is a shiny white. The filter took out all the fine algae that was in the water (which the photo does not really show), but obviously did not take out the tannin color. That’s okay: tannin doesn’t hurt. The pumping action was not difficult over this volume.

This test was done using the Nalge bottle connector, into a two-liter rectangular Nalge bottle. It was not the easiest way to use the pump: I had to drive it between my arms, with the bottle hanging off one end. It was clumsy to do and hard work after a while. From experience with many other filters, I know it is much easier to pump downwards, with one end of the pump on the ground. That method lets me use my shoulder muscles to drive the pump, and it is much easier with this pump, too.

However, pumping vertically means I can’t use the Nalge connector. Instead, I used a length of silicone rubber tubing to go from a spigot at the outlet into the bottle. The hose is visible in the next photo. I found when doing this that the hose MSR uses on this filter is actually slightly larger than that used on some other filters, and that smaller hoses will slip off the spigot fairly easily. But a bit of the hose supplied by MSR sticks on fairly well if pushed on firmly.

Having an outlet hose in place means that the filter can be used vertically. If you try to use the filter with the inlet at the top, you will never get rid of all the air in the pump. It will remain there as an energy-sapping ‘air-spring’. Always have the inlet at the bottom: the air will be at the top and will get quickly flushed out in a couple of strokes.

What the vendors never mention about routine operation of a filter is that the cycling pressure and flow in the inlet tube can make the pre-filter dance across the water. It happens to some degree with this filter too, with the added complication that the pre-filter can easily flip upside down. What I usually do when using such a filter pump is to lock the inlet hose down somehow: with a rock or my foot. The pre-filter still dances, but it stays in one place. Just don’t hold the tube too hard or you will squash it.

Then I tried the back-flushing process. The bottom valve, in the rounded inlet housing, is tricky to reverse. It has to be put back in very square to get the valve bit into the recess provided. The other valve, at the middle, is easy to reverse. Both get easier with practice: it is not a problem.

MSR shows a diagram of the filter with a Nalge bottle attached and inverted for the back-flushing process, but they fail to mention that the connection between the outlet spigot and the Nalge connector is not sealed. As mentioned above, it can leak all over you. I used the outlet hose I had rigged up to feed clean water from the Nalge bottle to the filter outlet, as shown in the photo above.

When starting to back-flush, there is usually air in the system, and the little filter tubes don’t like passing air. It is hard to flush the air out of the pump, and MSR recommends that you flush any air out the inlet tubing first. I found that the best way to hold the filter during back-flushing is as shown in the photo above: ‘upside down’. Doing it this way puts any air in the system at the top, where it gets flushed out quickly.

Even so, sucking water back through the filter requires that you pull upwards on the pump section (the top red bit), and this is much harder than leaning downwards on the pump to push down. If you try to do this too quickly you can get air leaks from the middle O-ring seal as well. If I pumped very fast I could get quite a vacuum in the pump chamber (half the volume in fact), and that seems a waste of energy. It is better to pump slowly. After a few slow strokes of the pump I managed to clear the air out, and by taking it slowly I was able to run the recommended half a liter of water back through the filter. It isn’t really difficult, just slow.

I was able to clean the flat red pre-filter very easily. I took the hose off the inlet and allowed the water in it to drain back through the pre-filter. Then I blew gently down the hose, making the pre-filter fabric bulge slightly. That seemed to dislodge just about everything. This is something I would possibly do every time I used the filter – at least it gets rid of the water in the hose.

The middle O-ring gets a lot of action, and needs to be lubricated regularly. For some strange reason, MSR does not include any silicone grease with the filter kit, although it is available in the recommended (and very comprehensive) maintenance kit.

Field Testing

We report here, three different rounds of field testing: in the field with clear water by the two authors and a more controlled test using dam water.

The photo here shows the Hyperflow being used with the Nalge bottle connector on a shallow clear mountain steam. There is some (harmless) iron bacteria on the bottom of the creek, but the floating inlet filter handled that excellently. You can see the inlet tube being restrained by the author’s foot: this kept it in place and stopped it from flipping. You can also see the awkward position of the author’s arms dictated by the use of the Nalge bottle connector.

The filter worked satisfactorily here over a couple of liters, but I would note that I probably would not normally bother filtering this clear mountain water. The inlet filter did pick up some of the red iron bacteria stuff from the creek bed, but this blew off easily when I back-flushed it.

Will Rietveld and his wife used the MSR Hyperflow water filter on three backpacking trips totaling eleven days. In his notes, he wrote:

"On each trip we solely relied on the Hyperflow, and all of the water we filtered was from clear mountain streams. First of all, it weighs a bit more than specified; we carried it in its zippered carry bag, and the complete kit (including a cap for a Nalge-type bottle) weighs 10.1 ounces, which is a bit more than the specified 7.4 ounces. So much for light weight!

From the beginning, the filter was fairly stiff to pump, and it has stayed that way. We back-flushed it after every trip, but back-flushing made no noticeable difference in its operation. Because of its stiff pumping and the need to pause briefly to allow the pump chamber to fill up, the pumping rate we achieved was about one liter per minute, much less than the three liters per minute claimed. The pump chamber filled up faster if we held it lower to the ground, but that made the pumping even more difficult.

Filtering directly into a narrow mouth water bottle required some downward pressure on the delivery end of the filter to keep it in position, which was a little awkward. The special cap provided that fits a Nalge-type bottle or flask works beautifully; we used it on a six-liter Nalge Canteen, then filled other bottles from the larger container. There is a fitting on the top of the cap that the outlet of the filter locks into, which helped to streamline the filtering process, especially for one-person operation.

Overall, we found the MSR Hyperflow water filter to be reliable, but laborious. At 10.1 ounces for the whole kit, it’s no lightweight compared to other filters, and it seems heavy and complex compared to chemical water treatment. Our main reservations about it are the higher force than expected to pump it, and the relatively slow delivery rate. For us, it was a lot less than hyperflow."

Thus both authors found that the Hyperflow worked reasonably well with clear mountain water, albeit with more force and more slowly than claimed.

Finally, a controlled test was done with my dam water, as described above. It should be remembered that the dam water is not crystal clear, but it is the sort of water you would want to filter if you had to use it. The cycles were as follows:

Filter 3 liters.
Pumping action started to get harder after 2 liters.

Back-flush with five good strokes.
The first two strokes were difficult, then it got easier.

Filter 3 liters.
Again, pumping got harder after 2 liters.

Back-flush with five good strokes.
The first three strokes were difficult, then it got easier.

Filter 2 liters.
These were harder to filter, and pumping at any speed collapsed the inlet valve several times.

Back-flush with ten good strokes.
These were hard to pump.

Filter 2 liters.
These were quite hard to pump, and the inlet valve collapsed several times.

While back-flushing, I found that it was easily possible to get half the pump chamber effectively holding a vacuum. I had to pull the pump up and then wait while water flowed through the filter to fill the pump chamber up. This could take a couple of seconds. Clearly the backwards flow was not good.

MSR says to back-flush with 0.5 liters (ten strokes) each time. In this test I only used 0.25 liters (five strokes). However, if I have to use 0.5 liters to clean out the filter after every 3 liters, then the whole thing becomes a serious waste of effort. I question whether there would be a lot of difference between the number of strokes I used and MSR’s recommendation anyhow. If five strokes won’t clear the filter, I doubt that ten would.

You will see my comment that the inlet valve collapsed during the testing. This means that the soft rubber flaps inverted, and let water go back out the inlet hose. This only happens when the pressure inside the pump chamber gets too high for the valve. I didn’t think I was exerting all that much force. This suggests that the design of the valves needs some attention. I see this as being a ‘Version 1.0’ problem.

Not mentioned above, I also observed that the outlet valve was doing something strange. When I pulled the pump back to refill the pump chamber with more water from the inlet valve, the water would recoil a distance up the outlet hose. I really do not understand what was happening there.

Finally, I tried using a Katadyn Hiker filter on the same water. The Hiker is widely regarded as the benchmark filter against which other filters are often compared. It uses a large pleated filter with a very long life, even on this sort of water. (I would expect to get at least 100 liters through it here, and probably considerably more.) The Katadyn Hiker was easier to pump than the MSR Hyperflow.

Summary

The design of the MSR Hyperflow is nice. The filter is light. But the filter element seems to be just not up to the task of handling anything other than clear water. To be sure, some ‘clear’ water can be problematic, and the Hyperflow does handle it moderately well. But that is not good enough for walkers who often have to handle a wider range of water quality with little in the way of choice.

My understanding is that MSR is very well aware of this problem, is concerned about it, and that there may be an updated version of the Hyperflow in the future. We look forward to seeing the updated version. In the meantime we cannot recommend this filter for use on anything other than clear water.

Specifications

What’s Good

• A fairly low weight
• Neat design
• Can be repeatedly cleaned easily – up to a point
• Useful inlet filter
• Cartridge and inlet filters can be replaced
• Removes bacteria and protozoa to EPA specifications

What’s Not So Good

• Quickly blocked with water which is not really clear
• Valve design collapses under pressure
• Nalge bottle connector is not ergonomic – and leaks
• Needs an outlet hose and hook added to the kit
• Unsafe for winter use when freezing is possible
• Silicone grease for the O-ring is not included with the kit
• Does not remove viruses (most microfilters have this limitation)

Editorial Addendum (02/06/09):

Note from the manufacturer:

We have identified a flow performance issue with some of the hollow fiber filter cartridges contained in MSR HyperFlow microfilters. The performance issue DOES NOT affect the product’s ability to filter safe drinking water, but can be frustrating, as the flow rate of the filter may not perform to product specifications. The issue has been rectified, and all filter cartridges currently in production for the MSR HyperFlow microfilter perform to flow specifications. We have worked with our retailers to replace units they have in stock that may have this issue. Any consumer that is experiencing less-than-expected flow rates on this product right out of the box or after back flushing is urged to call us at 1.800.531.9531, and we will send a valid replacement filter cartridge at no charge if the original was manufactured prior to November 11, 2008. (Please have the filter element handy, as we will ask for the serial number for our records and manufacture date verification.)

Introduction

The Six Moon Designs Refuge and Refuge X are the lightest two-person shelters by Six Moon Designs. The two tents are identical in size and design, with only minor differences in guyline and stake adjustments and a slight difference in vestibule coverage. The largest difference between these tents is in the tent body fabric – the $260 Refuge is made of silnylon and weighs just over 1.5 pounds, while the $400 Refuge X is made with a Cuben Fiber body and weighs under 1 pound.

Both single-wall tents offer excellent usable space and plenty of room for two large hikers. They use trekking poles or optional carbon fiber poles for support and have an integrated, non-bathtub floor.

What’s Good

• Very lightweight for a two-person single-wall tent.
• Refuge X is extremely lightweight, at under one pound.
• Enough usable space for two to comfortably sit up or tall hikers to stretch out when laying down.
• Excellent ventilation.
• Uses trekking poles to save weight (or optional carbon fiber poles).
• Quick and easy setup.
• Usable vestibule with sufficient space for two lightweight packs.
• Easy side entry.

What’s Not So Good

• No bathtub floor – less protection from dirt, splashing rain.
• Mesh at stake points and perimeter is susceptible to damage.
• Difficult to get a taut pitch on the Refuge X ridgeline.
• Poor wind stability.
• No interior storage pockets or hang loops.
• Refuge X is very expensive, at $400.
• Stakes are not included.

Specifications

Performance

The Six Moon Designs Refuge and Refuge X are nearly identical tents in design and features. Besides a few minor differences (explained below), the main difference between these tents is the fabric used in the tent body; the Refuge uses 30 denier silnylon while the Refuge X uses Cuben Fiber.

The Refuge tents have similarities to the Six Moon Designs Lunar Duo, including side entry, trekking pole support, integrated floor with a perimeter mesh, high vents, and a spacious interior design. With floor dimensions of 90 by 48 inches, the Refuge is equal in length to the Lunar Duo but is 6 inches narrower. To save weight, the Refuge is also a simpler design, with less features (single door and vestibule, no interior pockets, no aluminum struts, no bathtub floor, etc.); the silnylon Refuge is over a pound lighter than the Lunar Duo at 1 pound, 9.2 ounces and the Cuben Refuge X, the lightest floored shelter on the market, at just 15.8 ounces.

Fabric Note: Cuben Fiber (typically used for sailboat sails) is a laminate of Spectra fibers between two films of Mylar plastic, so it’s not woven.

In comparing the Six Moon Designs Refuge and Refuge X, the largest difference is the fabric used in the tent body. The Refuge uses a 30 denier silnylon while the Refuge X uses a 0.75 ounce Cuben Fiber. The Cuben Fiber fabric drops the overall weight of the tent by 37% (25.2 ounces to 15.8 ounces) while increasing the cost by 53% ($260 to $400). However, there are other differences between these fabrics that make these two tents unique.

It is well known that silnylon is a fabric that can stretch to some degree. In the field, that means that if the ridgeline of the silnylon Refuge is not quite taut, tightening the guylines just a little bit more can stretch the fabric and achieve a taut pitch. The side guyouts on the silnylon tent also create a larger interior space because the fabric stretches to a greater degree. On the other hand, the silnylon tent can sag through the night, requiring occasional re-tensioning. I also found that the tent tended to ruffle in the wind more than the Cuben fiber version.

Cuben Fiber, on the other hand, has almost zero stretch. With the Refuge X, it was easier to achieve a taut pitch, and there was no detectable stretch to the fabric in cold or wet conditions. The side panels did not stretch as much as the silnylon Refuge, but once set, the side panels remained drum tight. On the other hand, the ability to stretch the ridgeline to make it taut is lost. In the case of the Refuge X, the way the beaks attached to the tent body didn’t allow the ridgeline to become as taut as the silnylon Refuge, no matter how much I cranked on the guylines. While the rest of the Refuge X was tensioned like a drum, the ridgeline would move around in moderate winds, decreasing the overall wind stability of the tent and undoing some of the extra stability that came from the low-stretch fabric. In this case, a ridgeline/vent design that worked fine in one material (silnylon) had a drawback in another material (Cuben Fiber).

In the months that I reviewed the two Refuge tents, I had them out in conditions ranging from high desert to lowland northwest rain forests to high subalpine camps in the Cascades. Overall, I was impressed with both tents’ storm-worthiness, easily surviving extended downpours. In moderate winds, with all of the guylines in use, the tents had reasonable wind stability, but did experience some deflection and flapping (more than the comparable but heavier Tarptent Squall, for example). I wouldn’t recommend either of these tents for very windy conditions.

In analyzing the ridgeline of the Refuge X and how I could never get the tension I was looking for, I decided to take a closer look at how the poles attached to the beak. Having the attachment point on the end of the beak means that the non-stretch Cuben fabric must be aligned perfectly to have a taut ridgeline – even a small error can put less tension on the ridgeline than on the tent body. To find a possible solution, I put the grip end of the trekking pole against the seam of the ridgeline and beak and found that greater tension was much easier to achieve. Although the current design has adequate ridgeline tension, moving the trekking pole attachment and redesigning the beak would increase the wind stability of this tent.

While wind stability may not be the forte of the Refuge and Refuge X design, usable space most certainly is. There is an amazing amount of usable space in these tents, especially when the side guyouts are used. My wife and I shared the tent with our two-year-old son, Henry, on several occasions, and found the tents to be sufficient to fit the three of us (when Henry slept on the mesh at the end of the tent). When waiting out a storm, the adults had room to comfortably sit up while Henry walked inside the tent and climbed on us – four adults could sit up and play cards in a pinch. There is also excellent length for sleeping in the Refuge; at 6 feet 1 inch, I’m a pretty tall guy, but when I stretched out from end to end, I was unable to touch the walls of the tent. In maximizing usable space per ounce, Six Moon Designs has definitely hit the mark with the Refuge and Refuge X – these tents are much roomier inside than other tents in their class.

The entry and exit of the Refuge is through one reasonably-sized door. The vestibule unzips and clips to the sides with elastic clips. The mesh door also rolls up and shares the same clip as half of the vestibule door, adding to the thoughtful simplicity of the design. The large mesh wall on the front of the tent makes for great views during fair conditions.

Ventilation on the Refuge and Refuge X is excellent. Two large covered vents at the top of the tent, along with perimeter mesh and an all-mesh front wall, create a chimney effect and excellent airflow. I found the Refuge tents to have the least condensation of any lightweight single-wall shelters I’ve used. Even during calm, high humidity conditions (a single-wall tent’s greatest enemy), the Refuge tents had very moderate condensation that was easily wiped away. I was very impressed by these tents’ condensation resistance.

The Refuge tents do not have a bathtub floor. A bathtub floor is a typical tent feature for many reasons – it keeps water out of the tent, offers increased splash protection when combined with mesh walls, and keeps dirt off of the tent floor. The Refuge tents work around this by having mesh floors that lift off the ground between 2 and 5 inches, depending on the length of stake out guylines. During field testing, I found that this design kept flowing water under the tent floor and provided sufficient ventilation. I also found that when adjusted correctly with longer corner guylines, the mesh rarely came into contact with the ground, keeping the mesh clean and mud-free.

That said, the seamless floor-to-mesh transition makes it very easy to slide or roll onto the mesh area, and on several occasions during testing, gear or a hiker’s body slid into this area. When this occurs, gear or a sleeping bag can become wet very quickly and ventilation is decreased.

During dry conditions, the large mesh areas increase the potential floor space of the tent, but the thin mesh is much less durable than the silnylon floor, so this is not recommended.

The Refuge tent directions call specifically for a 45-inch (114-centimeter) trekking pole, and that’s exactly what the tent needs to be set up as intended. The pole handle slips into a small pouch at the base of the tent (one in front and one in back) and attaches to a grommet at the top. This exact length creates the ideal tension, and a longer or shorter pole negatively affects the tent setup. This is very easy to achieve for those that use adjustable poles, but it can be a limiting factor for those that use fixed-length poles. I found that it was possible to use a longer trekking pole if I didn’t use the handle pouch and used a small guyline and stake to extend the front attachment (this is also a trick to increase headroom). However, this creates the need for two additional stakes and guylines and adds a step in setting up the shelter.

The style of guyline adjustments at the front and rear beak are different between the Refuge and Refuge X tents. The silnylon Refuge has a nylon guyline with integrated plastic adjuster, while the Refuge X has a short section of webbing with an adjuster and lighter fixed-length guylines (included). The difference in usability is minimal, and I assume the change with the Refuge X was an attempt to shave some grams to hit the sixteen ounce weight goal.

Another difference between the two tents is the length of the vestibule wall. While the Refuge comes to nearly ground level, the Refuge X is about three inches higher above the ground. The difference in gear coverage or increased ventilation was very minimal.

The last difference between the two tents (besides fabric type, main guyline adjustment, and height of the vestibule wall) is the stake adjustments. The silnylon Refuge features adjustable stake attachments that make re-tensioning a breeze. (Keep in mind – the webbing straps are not sewn at the end, making it easy for them to slide out of the plastic adjuster, so be careful not to lose them!) When setting up the tent, I recommend starting with the straps adjusted to their longest length and tightening them as the silnylon sags; this way you maximize the height of the perimeter mesh off the ground.

The Refuge X has simple corner loops that require separate guylines (included with the tent) with no adjustor – presumably to cut a bit more weight. This requires repositioning the stake to change tension, rather than using a simple adjustment as in the silnylon Refuge. Again, using a longer guyline is preferable to keep the mesh off the ground.

Both tents feature diminutive YKK zippers that performed flawlessly during testing. Storm flaps cover the zipper and a Velcro tab keeps the rain flap closed and takes tension off of the zipper.

The vestibule measures approximately six square feet, which is sufficient for two ultralight packs, shoes, and a few other items.

While some may question the durability of the extremely lightweight Cuben Fiber used in the Refuge X, I found this to be an excellent material for use in a tent body. Cuben Fiber is waterproof and extremely strong and stretch resistant – its weakness is in puncture and abrasion resistance. Six Moon Designs was intentional in using this as a fabric in the tent body but sticking to 30 denier silnylon for the tent floor, a combination that plays to the strengths of the two different materials. Still, if durability is a concern, you may want to go with the silnylon Refuge.

A couple of durability concerns did come up with the Refuge tents. First, mesh is used at the base of the corner stake out positions. When adjusted too low, the mesh comes in contact with the ground, where dirt can get into the material. In one corner, the abrasion caused a small hole. I would recommend additional reinforcement in these corners.

I have a similar concern for the entire mesh perimeter – if the tent is staked too low, the fragile mesh comes in contact with the ground, causing a potential durability concern. While proper pitching with long corner guylines can alleviate this problem, rolling onto the mesh also has the potential to cause damage.

Cuben Fiber requires additional reinforcement at seams that are under tension. On the Refuge X this only occurs at the junction between the tent body and the beak, and it’s reinforced with seam tape. After several months of use, the seam tape started to peel up at the edges. While I don’t believe that this will peel all the way off or lead to a seam failure, this is a spot that a Refuge X user will want to check periodically.

At $260, the Refuge tent is reasonably priced and offers excellent usable space, effective ventilation, good views, and a functional vestibule – all for just over 1.5 pounds. At $400, the Refuge X is a very expensive tent. However, it features low-stretch and very strong Cuben Fiber material and a weight of under one pound – a first for a two-person floored shelter. Depending on your priorities, both Refuge tents offer a good value.

What’s Unique

The silnylon Six Moon Designs Refuge tent is a reasonably priced, two-person shelter that has incredible usable space for a weight of just 1.5 pounds. Released alone, the Refuge tent would be a welcome entry to the market.

As far as uniqueness, however, the Refuge X steals the show. It is the first Cuben Fiber, two-person tent on the market and is currently the lightest two-person floored tent, at just under one pound. It’s not just an experiment in light weight, though – after several months on the trail, the Refuge X has proven its worth as a shelter that is both usable and durable.

Recommendations for Improvement

• Consider moving the pole attachment to the tent body and redesigning the beak for greater ridgeline tension.
• Reinforce the mesh under the corner stake out points.
• Consider using a bathtub floor or attaching the perimeter mesh further up the side of the tent walls to get them above the ground.

Introduction

The previous generation 2006 Gossamer Gear Lightrek pole was a staff favorite and received the highest rating among fourteen poles reviewed in our 2006 Carbon Fiber Trekking Pole Review Summary and Gear Guide. They were comfortable to use, had excellent grips, and were incredibly light. However, the Gossamer Gear poles did have some drawbacks – they were more flexible than other poles and had a bad habit of losing baskets on the trail.

The new Gossamer Gear Lightrek 3 poles address both of these concerns and have some major improvements over the previous model. The poles feature all-new shafts that are made of tapered carbon fiber that are both larger in diameter and significantly stiffer than the previous models. They use the same excellent grips but a better Leki-style tip is used. The best news about all of this is that the weight remains exactly the same as the previous Lightrek (2.8 ounces in a 125-centimeter length), making these poles the lightest on the market once again.

What’s Good

• Much stiffer than previous Lightrek poles and comparable to other poles on the market.
• Excellent vibration damping and a comfortable amount of shock absorbing flex.
• The lightest poles on the market at 2.8 ounces (79 grams) in a 125-centimeter length.
• Molded EVA “Kork-o-lon” grips are comfortable and offer multiple hand positions.
• Use common Leki-style screw-on baskets.

What’s Not So Good

• $130 is more expensive than previous Lightrek models (but comparable to other carbon trekking poles).
• Not as stiff as some other trekking poles.

Specifications

Performance

The Gossamer Gear Lightrek 3 are fixed length trekking poles. Since the first generation Lightrek, Gossamer Gear has held the title of “lightest trekking pole”, and at 2.8 ounces in the 125-centimeter length, the Lightrek 3 continues this tradition. While previous Lightrek poles were too flexible for some users and tended to be on the fragile side, the new Lightrek poles tackle this and other issues, all while retaining their ultralight weight.

The major news in the Gossamer Gear Lightrek 3 are the all new shafts. While the last generation Lightrek poles had a straight shaft diameter of 1.0 centimeter, the Lightrek 3 shafts taper from 1.4 to 1.1 centimeter, an increase of nearly 30% in the thickest portion of the shaft. The result is a pole that is significantly stiffer (see results below) while keeping “swing weight” lower at the tip end of the pole. All Lightrek 3 shafts are now produced in the United States.

Also new to the Lightrek 3 poles are carbide tips that accept Leki-style screw on baskets. While the previous model also used screw-on baskets, the baskets tended to come loose while hiking and were easily lost. The new tips eliminate this problem by placing a non-threaded area above the screw-on portion of the tip. This allows the baskets to rotate without unscrewing and after several months of testing, I haven’t lost a basket yet. The poles come with small two-inch trekking baskets which are highly recommended when hiking in rocks or long boardwalks. The poles are compatible with a variety of widely available Leki baskets; I’ve used the large Leki snow baskets on many occasions with no issues.

The multi-position EVA “Kork-o-lon” grips remain unchanged from the previous Gossamer Gear Lightrek poles. This is good news because these grips offer three usable hand positions, adding comfort during extended uphills or steep downhills. They have a nice cork-like feel and don’t get slippery in wet or snowy conditions. I’ve now used Kork-o-lon grips on three different sets of poles and they remain my personal favorites.

While some may miss the security of a wrist strap, they really are not necessary with a pole this light. A light hand pressure is all that’s needed to keep the poles in your hands in technical situations, and the Kork-o-lon grips allow for quick hand placement changes when climbing or descending. Further, not having the poles attached to your hands can save the shafts from possible breakage when leveraging them between rocks or in the grooves between wood slats. For times when you can’t afford to drop a pole, such as high angle snow crossings, small loops at the base of the grips allow wrist loops to be attached to the poles. Tent guylines make excellent improvised loops in these situations.

One disadvantage of fixed-length poles is that they are not quite as versatile when used with shelters that require trekking poles. Angling the poles, digging small holes to set them in, or setting poles on rocks to extend the length can often help to overcome this issue.

At only 2.8 ounces in the 125-centimeter length, the Gossamer Gear Lightrek 3 is the lightest trekking pole on the market. A pole this light is a pleasure to use, making for quick placements and significantly less fatigue at the end of a long day. They are, quite simply, a joy to hike with.

Older Gossamer Gear Lightrek poles were known for their excellent shock-absorbing flexibility but they were also less stiff than most other poles on the market. With the new over-sized and tapered shafts, stiffness of the Lightrek poles has increased significantly. Using our new 2008 Backpacking Light Pole Stiffness Test, the Lightrek 3 poles were supported in a fixed rig at a 100-centimeter length with a twenty-five-pound load suspended from the center of one pole. Pole deflection is then measured using calipers. While the previous generation Lightrek 2 poles deflected over 9.0 centimeters and exceeded the maximum deflection of the testing system, the Lightrek 3 poles deflected a much more moderate 5.1 centimeters, an increase in stiffness of more than 40%. While this deflection is still more than some other poles we’ve tested, they are now comparable to most trekking poles on the market and have a confidence-inspiring, non-“noodly” feel – impressive for a pole this light.

On the trail, the Lightrek 3 poles have a very comfortable balance of stiffness and flexibility. They feel reasonably stiff when pushing off, adding efficiency during high mileage days and inspiring confidence during tricky descents. They are also very comfortable on the trail, flexing somewhat when absorbing harsh impacts. This balance between rigidity and flexibility was very functional.

In addition to being stiffer than previous models, I also found these poles to be much more durable. Despite many months of serious use, ranging from snowshoeing to off-trail scrambling to trips carrying 50+ pound loads of a child and gear, the Lightrek 3 poles had zero durability issues. I was very hard on them and never felt the need to treat them gently (except when avoiding placements between rocks or wood slats – a real danger zone for trekking poles). These are poles I feel I can really count on.

With such a solid performance increase and no increase in weight, there must be a catch somewhere; in this case, it’s the cost. With the Lightrek 3, the cost has increased from $96 to $130 – ouch! That said, improved stiffness and durability and a much more usable tip make this a worthy increase. When compared to other poles in this class, the Gossamer Gear poles are still an excellent value and a purchase that I would highly recommend.

What’s Unique

These are the lightest trekking poles on the market and they have increased in stiffness more than 40%, while having a weight increase of exactly 0%. The added stiffness and durability makes them poles that would satisfy the needs of both ultralight and traditional backpackers. They are stellar performers.

Recommendations for Improvement

All of my complaints of previous Gossamer Gear poles have been addressed with the Lightrek 3. After testing a prototype pole that had even larger shafts, I feel that Gossamer Gear has found a real sweet spot in pole performance with the Lightrek 3. I wouldn’t change a thing.