Good ~50L pack with “trampoline” (off the back) suspension and extension collar?

About that Osprey pack…
If it fits you well, you're going to love it.
My only gripes are the nearly unusable hip belt pockets, and the center of gravity.
Careful packing will manage the COG issue, and I can deal with the pockets because I LOVE the way it fits me.
There's a drawstring top with a flap, and the generously sized lid with two big pockets can float up quite a bit so you can stuff something under it. Like a foam sleeping pad.
The trekking pole attachment is awkward; I just use the ice axe loops instead.

I have an early model Atmos 50, gray, size medium that I'd like to sell ($50 + shipping). PM me if you are interested.

I picked it up at an REI garage sale but it didn't fit me well (the shoulder straps are too far apart for me). One of the front pocket zippers doesn't close very well (probably why it was returned) but the pack showed no wear whatsoever and I've only used it once (3 day trip).

I would have sent it to Osprey to get the zipper fixed if I was going to keep it. (If they can't repair it, they will replace it: http://www.ospreypacks.com/en/web/all_mighty_guarantee).

Note that on the early models, the suspension intrudes more into the body of the pack but it handled my BV500 for (vertically) the trip.

But I did like the suspension so much that I bought a new one last year. Comfortable and plenty of hauling capacity when I'm with my daughter (who can't carry much). I find that there's a lot to like with this pack.

– Steve

52L/60L with trampoline "off-the-back" suspension. Hybrid cuben or dyneema fabric. Not cheap, but very light.

Have you taken a look at the Osprey Exos? It is considerably lighter than the Atmos AG, but has the trampoline back you're looking for. It has become my bag of choice, at least so far.

It comes in 38, 48, and 58L sizes.

It doesn't have an extension collar, though. The top is drawstring, and it has four zippers: two hip belt pockets, outside lid, and inside lid.

#1 on the EXOS 58. I love mine.

I often hike where it is sorta warm.

Over the years I have tried packs with suspended mesh panels to reduce sweating. When I started backpacking almost all packs were external frames with mesh panels. Then I went to internal frames. Then to try and reduce sweat I tried a Dueter internal and an REI Venturi.

Conclusion: suspended mesh panels move the load away from your center of gravity. No matter what kind of pack you use, you are going to sweat. Best strategy is to accept the sweat. You can't minimize it. If you just accept the fact you will sweat, you learn to ignore it.

Thanks for the intel! Why are the hip pockets unusable? Could they at least fit something like a leatherman on one side and a 5" Galaxy S4/S5 in the other?

The drawstring top doesn't telescope or expand further, huh? Being able to stuff a chunky foam pad under the top pocket is pretty good though.

When you remove the top pocket does it become a small fanny or daypack? I can't seem to figure this out from the Osprey documentation.

It would be kind of worthless being able to remove the top pocket but then simply having essentially a loose bag that you can't attach anywhere else…

Haha, I'm in China at the moment so logistics would be an issue. I'm also probably bordering on a small to medium size since I'm 5'5". Ideally I would still like to try one out in the store.

Good to know about the great repair policy though.

On both the new and old packs, are the zipper teeth and/or actual zipper made out of plastic or metal? Like I said, I've had zippers corrode shut before and I even had to take a knife to the pack to get at the contents. And I've also had older zippers simply not zip shut anymore. Truly a pain in the ass – I much prefer cinch strings – and you can knot them shut for security as well.

Wow, the Exos looks fantastic and the weight is lighter than my Granite Gear and the capacity is around the same while having lots more features.

Actually, I can't tell the difference between the Exos and the Atmos AG. The weight and the capacity aside, they both seem to have the same features except the Atmos has access to the bottom portion of the bag via a zipper. But otherwise, both have trampoline suspension, tool loops, pole attachments, belt pockets, detachable top pocket (can it be used as a daypack???), sleeping pad straps…

Wow, impressive. But I agree that they are very expensive. If I spec out one of their packs to include the features of the Osprey (hip pockets, pole carriers, etc) they come close to or more than $400. That's almost twice as much as an Osprey while also being considerably uglier, haha. But I DO really like that roll-top closure…

I haven't tried the Atmos AG, so I can't make a direct comparison, but here are some features the Exos lacks in order to shed weight. None of these are bothersome to me in anyway, but everyone's needs are unique.

– Top loading only; no zippered panel. I haven't missed this, but I suppose a panel could be convenient. But I've found using the lid, large back mesh pocket, and packing sensibly, that I've got easy access to the gear I may need while on the trail, so a panel is not a something I feel the need for at all.
– The lid is removable, but doesn't have a hip belt like some other packs, so it cannot be worn as a hip pack.
– Torso length is not adjustable. This may a big advantage of the Atmos, depending on how well the Exos fits you. Hit again, I haven't missed this compared to my previous packs.
– Compression straps are very thin, but plenty strong and durable in my experience.
– Lighter weight fabrics may not be as durable. I, unfortunately, don't get enough days out to really torture my gear, so this isn't an issue for me, and it's plenty durable for my needs.

"No matter what kind of pack you use, you are going to sweat. Best strategy is to accept the sweat. You can't minimize it. If you just accept the fact you will sweat, you learn to ignore it."

+1

"No matter what kind of pack you use, you are going to sweat. Best strategy is to accept the sweat. You can't minimize it."
I'm afraid I can't agree with this – you can minimise it. With the Arc Blast, if I had a journey where it was going to take some abuse (thrown into bus holds, crammed into the back of minibuses), I used to travel with its back unsprung as I felt it was less likely to get damaged that way. Then the first day, I'd have the pack flat against my pack. Believe me, the next day, with the back bowed and letting the breeze through, it would really keep you cooler. Yes, you're going to sweat if it's hot, but not as much.
I also think the centre of gravity argument is a bit of a red herring. Yes, a trampoline will move the centre of gravity away from your back, but so will any back padding, or a burrito style rolled up sleeping mat etc. The padding probably extends all the way down your back too, including the shoulders. One of the nice things about the Zpacks sacks is that you can adjust how much the trampoline is bowed if you want to bring it closer to your back.
Furthermore, it's not just the back system that affects how far from the body the centre of gravity is – the shape of the pack will affect it too. The Arc Blast is relatively wide and shallow. My wife's Arc Blast, even with a decent bow in the trampoline, places the centre of gravity much closer to her back than her Golite Jam 2 does.

Worth every penny, but I did not ask for more than the standard model. Love mine, and I'm hiking currently in 90-100 degree heat. The trampoline/mesh is sooooo nice, a slight breeze cools my back when I'm soaked, and if I don't want it bowed I have the option. The load carries great regardless. In fact I often forget about it.

I would have to agree, at least the way the Exos 48 fits me, that I have no issues with center of gravity over previous packs I've owned relying on foam padding for support or to channel heat away from the back. I was skeptical at first about tramp backs but I overheat easily and when I felt the cooling breeze on my back it was truly impressive. The pack does well with support for my injured lower back and is fairly lightweight. I didn't buy the pack for its ability to cool my back but it was a big plus.

The idea of the detachable top is just to loose some more weight. I leave it at home now and use a UL mesh bag for all my small stuff instead of using the top.

Also FWIW I was not too thrilled with the torso adjustable pack I owned. Seemed like a good idea at the time but gave me the impression it was a short cut to a good fitting pack. Much happier searching out a non adjustable with good design for my body config.

jimmyb

I bought an Atmos AG earlier this year, and I previously tried the Exos in the store. I'm considering returning the Atmos.

I noticed the Exos doesn't handle weight as well as the Atmos. I tried it before I discovered lightweight backpacking, and with a 35lb load (max I anticipated) I could feel the frame flexing as I picked it up and wore it. These days my base weight is lighter, but I want to be able to do longer trips, so I might still want to carry 30-35lbs sometimes. I think the Exos could handle it sometimes, but it's hard to tell if you would sacrifice some comfort.

There was a question about the hip belt pockets on the Atmos. Because of the curvature of the belt, and the shape and size of the zipper and pockets, it's difficult to fit anything in them or open them to get stuff in/out. The curvature holds the zipper together, so it's not a big opening. Maybe a small ziplock bag of snacks would fit. A leatherman would probably fit. I don't think a 5" smartphone would fit comfortably.

There are a few things I don't like about the Atmos. First of all is the weight. It's 4lb 6oz for a medium. If you get it at REI you get a free rain cover and dry bag. The rain cover is 4oz, and I didn't weight the dry bag, but it's probably around 0.8oz like my other one. If you carry these, and if you would not otherwise, then you are over 4lb 10oz.

My torso length measures at 19, but I like to wear the hip belt lower sometimes, so sometimes I like the torso slightly longer. I also like relatively little weight on my shoulders. I can't remember where it was initially set, but I think it slipped a bit because after the trip it was set for 21. With it set at 21 (max listed for medium, but it can go 1/2" past there) there's not enough adjustment in the load lifters to get it all the way against my back. And the shoulder straps have to be tight. The load lifters are stiffened straps, and the hip belt is very springy, and as a result it's really difficult to put the pack on.

Center of gravity seems to be a problem even though it's not much farther out than my padded back panel pack. I don't know what it is, but maybe it's the curvature of the pack. It seems to pull back on my shoulders/collar bone and push into my lower back more than it should. If I pack carefully I can get it to be acceptable, but it's not as nice as my old REI Mars 85 that I can pack however I want with any amount of weight and have it sit comfortable upright with most of the weight on my hips. It's better than the old design Atmos packs for me, though.

Because of the curvature of the frame it can be a bit difficult to pack to the full capacity. It's big enough that it's not really a problem, but I have a similar 36L pack (stratos) and it doesn't hold much stuff for its size unless all your stuff is soft.

A friend brought his Stratos 36 on an overnight trip (he doesn't have a real pack) and he was complaining about it the whole time. That one isn't meant to carry a lot of weight, and if the Exos design is similar I would be concerned about using it with much load at all. The Stratos is about a 3lb pack.

Hi,

I hike alot in Negev Desert. Here the high temps jump over 100F occasionally and I must say, mesh back is a MUST for me. I tried all kind of packs and now for day hikes I take Gregory Z30 which is a luxury at 5lb, but for one day I don't take alot, so this doesn't bother me. My ZPacks Arc Blast is on the way for my upcoming 10 days hike in Swiss Alps.

Just my $0.02

Atmos had a redesign a couple years ago, so dislikes from before that don't necessarily apply(I didn't like the older version at all-don't know about the newer one).
The Exos series is my choice over anything on the market, and I tried just about everything before buying. That has nothing to do with whether it will fit and work well for you, just sayin'.
I like some of the Gregory packs(Z series?) that have mesh backpanels, too. They're heavier, but would probably carry more weight comfortably.

A suspended mesh backpanel absolutely does minimize sweating. That's the whole reason I switched to packs that have them, and don't bother to look at packs that don't. A river of sweat pouring down my butt in February with just a t-shirt on initiated that switch in suspension types for me, and I lived happily ever after-the end :)

Add another vote for Exos. I have the 34 and 58. best to find them when they are on sale.

As mentioned above, the hipbelt pockets are tight. The goofy adjustment system just takes up too much space where the pockets want to be. Small tools, lip balm, maybe some trail mix. That's about all that will fit.

For your zipper issues, try paraffin wax. When I was in the Navy, we would melt it carefully in a double boiler (it's flammable) and apply it with a small brush to the metal zippers on our utility jackets. There may be other substances that work as well, but that's what we had and it worked.

I returned my Atmos AG today and checked out the Exos 58 again. The frame is MUCH stiffer now than what I remember (I think I looked at it about a year ago, not sure if it has changed). There is almost no flex if you set it on the ground and press on it from the top. My Stratos 36 feels like it will snap in half if I do the same, and I think the Atmos was somewhere in between (though they didn't have an Atmos nearby to compare). I think it's stiffer than the Atmos AG frame, but the Atmos could still carry weight better because the hip belt is more substantial. I didn't have a chance to load it up, but it could be a good option.