Mont Bell SS down hugger

I expect that you will get a lot of positive responses on this one. Montbell down bags seem to be a favorite on here.

I have the #3 and I don't think they exaggerate on their temp rating at all. Somebody posted a link that had the Montbell bags on sale on the board somewhere.

Kirk

Darren, I own three Montbell bags, and I compared a few of them carefully before deciding which # bag to keep.

General recommendations:
In my experience the temperature ratings are spot on. And I can push the rating 5'C colder by wearing a thin wool base layer and watch cap.

The patented super stretch ("SS") system (elastic circumfrential baffles) does several good things.
1. Separates the inner and outer shells so as to maximixe loft continuously and automatically.

2. Lightly hugs the users body to minimize internal air gaps; thus preventing 'pumping' out of heated air.

3. Allows the bag circumfrence to stretch up to 50%, to 75.6"(192cm) in the shoulders for the long bag. You wanted a "roomy" bag; find any others that stretch to 192cm?? The hips and leg areas also stretch of course.

No other bag has this full-length system, because Montbell patented it.. other bag makers are torn between making the bag slimmer to reduce air gaps, and wider for increased roominess. Some people don't mind a constricting mummy bag, but Montbells design simply avoids this dilema with the stretch baffles.

Specific recommendations:
Get the #5?
If you are really only going down to 5'C, the #5Long bag (6'C,575g) is a great choice, and you could wear a layer to push it below 5'C. BUT, why not get the #4 or even #3 if it is your only bag; you will have much more temperature range at a small weight penalty.

Get the Long
I strongly recommend the Long bag for the extra room, and the space to put in boots, water bottles(so they don't freeze), even another person in an emergency. I can actually sit up cross legged in my longs.

Consider the "Alpine" version
Be aware of this lighter variant, but its less roomy so I dont recommend it as an only bag. These still have the inner baffles, but the outer ones do not stretch, so the overall bag does not stretch as much. I have a #7A and it is so light (450g) I toss it in my pack on day hikes where an unplanned bivouac is possible.

What I got..
I bought with a #7L for three season use, and a #3L for winter use. I expect my insulation clothing to push the bag rating down 10'C if needed.

Important note; these bags have square baffles which contain the down. This keeps it in place for the SS system to do its job, but you need to fluff up the bag for a few seconds to get the down to completely fill the chambers.

Here's a copy of the MB temp rating chart..

I own two MontBell bags — the lighter weight, non-super-stretch versions — and am very happy with those as well. Echoing Brett the MontBell pimp above, I too find their weight and temp specs to be accurate.

Click here for an English translation of the above temperature chart.

They're not visibile in the English translation, but the Chinese character graph beneath are suggested mountains around Japan for where the bags are appropriate during the height of the winter (blue) and summer (red) walking seasons. The highest is Mt. Fuji because it has the highest altitude.

Thanks, Miguel. I only wanted to show the temp ranges, but yes, that temperature chart is actually quite interesting because it incorporates latitude, altitude, and season into a prediction of the low temperature; probably based on historical data. Japanese catalogs seem to present information with a little more technical detail than I have found in comparable US catalogs.

Thanks Heaps
Im going for the 4 long , there on special at prolite at the moment. I have a macpac latitude 700 for real cold ,A great bag but 1200g very heavy, but we all make mistakes!!
Thanks again