| Size | Short | Regular | Long |
|---|---|---|---|
| Shape | Mummy | Mummy | Mummy |
| Weight | 1 lb. 13 oz. | 1 lb. 15 oz. | 2 lb. 1 oz. |
| Fill Weight | 17 oz. | 19 oz. | 21 oz. |
| Fill Type | 850+ Power Goose Down | 850+ Power Goose Down | 850+ Power Goose Down |
| Temp Rating | 20 degrees | 20 degrees | 20 degrees |
| Packed Size | 7 X 13 in. | 8 x 15 in. | 8 x 15 in. |
| Shoulder girth | 63" | 64" | 65" |
| Hip girth | 56" | 56" | 56" |
| Foot girth | 39" | 39" | 39" |
| Height | 5'6" | 6'0" | 6'6" |
REVIEWS
36 Reviews
Isonychia
Western Mountaineering sleeping bags are the best. I'll be economically minded on everything else, but if I sleep poorly, especially when it is cold and wet as it often is in the Upper Midwest, I'll immediately regret not having the best sleep gear. Not unusual to have a weather report state 40 degrees and something rolls in, and you are looking at high teens. Be prepared.
Casedog
Top tier equipment! No regerts! Most lofty, comfortable, and expensive bag you’ll ever buy Life is too short for cheap gear! Treat yo self!!
Rose
High quality construction, sure to last. Comfortable, fits me will (6’,150). Warm for its rating, packs down nicely, and is light for its warmth. Highly recommended.
Truu
I have borrowed this bag from my dad for a number of trips and I finally invested in one for my wife (sleeps cold) for 2 weeks in the andies. First speaking of my dad’s experience: he’s had this bag for over 15 years, and slept in it more than 100 nights outside of a tent in alpine temperatures ranging from 10-50 degrees, and never had an issue with it. Still lofts like the one I just bought. My wife’s experience sleeping in 15+/- in the Andies: kept her warm enough and very cozy. The only drawback you can come up with for this bag is the price, but at the end of the day you will get what you pay for. When you’re ready to buy your last sleeping bag, buy this one.
Brandon11993
Both incredibly light and warm, this bag DELIVERS. The only complaint I have is that the bag is a big tight in the feet and knees however that is by design to lock in warmth. Used this bag in low 30s with nothing but a t-shirt and underwear and stayed toasty warm.
KR53
I have a WM zero degree bag and 30 degree bag, but I feel the cold more now that I am nearing age 70. The 20 degree bag hits the sweet spot for cold nights, packability and versatility. As always, WM quality is unsurpassed.
MarkO
I have been a cold sleeper until this bag it’s pricey but definitely worth it, packs down very well. And roomy enough it’s very light weight for the temperature rating
MrTR
I’ll start this off saying I have tested this bag for about a year now. From very cold alpine Idaho spring weather to hot southwest desert fall, to camping when it was near 0 degrees. No complaints at all. This bag is worth the price. I spend many nights a year in a sleeping bag, most of which are usually out under the stars without a tent and only on a pad. I have several other bags for other temps and this one has become my go to for anything from 50 degrees down to around 10. They advertise “20 degree” but it has worked well under that temp for me. I use a thin sea to summit liner in my bags to keep them cleaner and it does add a little warmth when it is colder. The bag is super lofty, it stays warm, and the features are just right. no extra bells or whistles but everything on the bag performs perfect. The zipper has yet to catch ever. The draw cord for the hood works perfectly to close it up as well as the draft collar cinch. The main reason I purchased this was for the lightweight and warmth for the high mountains. Mainly for backpacking, alpine climbing trips, and even car camping . The weight for packing it in is wonderfully light compared to the bag I had been using (nemo sonic) and it packs down very well to pack in a backpack. I haven’t had the bag in any significant rain yet but it has seen a number of very frosty or dewy mornings in the southwest desert and the mountains of montana and Idaho. All in all 5 star product by a great company. Well worth the money . If you spend any large amount of nights in a sleeping bag or want the best you can get this bag is it. And it is backed by a great warranty and customer service. Im already looking at the Western Mountaineering 0 degree bag for backcountry ski trips.
Susan
I bought this sleeping bag for Fall backpacking trips. I normally use a a quilt, but I wanted something a little warmer. I had a chance to test this on a recent trip to the Emigrant Wilderness and I was very pleased with the performance. Warm, wide enough so that I didn’t feel claustrophobic, and the zipper did not get stuck! So important in the middle of the night! The quality of this product is exceptional. Highly recommend.
Alfred
I’m convinced Western Mountaineering makes the best bags you can buy. The design, materials, and craftsmanship are all superb. It seems markedly warmer than other bags with similar temperature designations and it’s roomy enough for side sleepers. Pretty much perfect.
All50states
I've now had a chance to test this bag out. Despite being lightweight, it is very warm and comfortable. In temps below 40, it isn't too warm either. If you plan to do any cold weather camping, this is an excellent choice for a bag. It is roomier than the Ultralite version and as a side sleeper and someone who likes to pull my legs up, it provides enough room. I think you could comfortably use this bag in the low teens. The bottom line is this... I've tried to be cheap before and ended up cold. Make the investment in this bag for many happy years of warm sleeping on cold nights. I've yet to find any shortcomings with this bag. Worth every penny!!
Mazz Man
I have used numerous sleeping bags in many settings. The Western Mountaineering bag is the best. Performs well in a wide variety of temps and easily met the 20 degree rating. Packs small and is easy to carry, deploy, and re-pack. I highly recommend.
Clint
Just got back from using this bag for the first time on my annual backpacking trip to the Wind River range in WY. An expected cold front and a little snow turned into an unexpected alpine blizzard. Temps dropped below 10 degrees a couple of nights, but this bag kept me toasty warm. In addition, two nights in a row my tent did not vent well after being half-buried by the blowing snow and considerable condensation and frost formed on the bag around the head and chest area. This caused me considerable worry as I have always used synthetic bags, but it did not penetrate to the down. Finally, the ample internal roominess was very comfortable, and helped ease the claustrophobia of being mummied-up in a one-person tent squeezed even smaller by the weight of snow.
holly3berry
I bought this bag a few weeks ago and took it for a test run camping and backpacking last week. Someone said in one of the reviews it's like sleeping on a cloud, and it truly is! The softness of the material, the fullness of the down, the option to draw in the baffle around the head and the actual head opening are perfect. I slept both with a pillow tucked into the head space and without. The night temps were low 50s, I worse a light, short-sleeve t-shirt and the bag was perfectly warm. I'm sure I could use it in much lower temps with added clothing and be comfortably warm. It's an expensive bag, but a lifetime bag and worth saving up for. Very light and packable, too, as an ultralight backpacker (8 lbs base weight). I've tried quilts, but any gap in cold temps leaves me chilled. Give me this full bag any day! Love it!
Astro
Colorado summer nights above tree line are pretty cold even if the days are warm and pleasant for hiking. The Alpinlite 20 is perfect for its small, packable size and weight but plenty warm at 40 degrees. Will see how it does this fall when the temps are in the lower 30s. I’m sure it will do the job.
Read All Reviews (36)
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