How to Choose Sleeping Bags for Backpacking

Find your ideal balance of space and warmth. With a customizable shape, the Therm-a-Rest Boost 650 20F/-6C sleeping bag transforms from a roomy semirectangular bag to a thermally efficient mummy bag.
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Imported.
Best Use | Backpacking |
---|---|
Tested Lower Limit | 20 degrees (F) - ISO |
Tested Comfort | 32 degrees (F) - ISO |
Temperature Rating (F) | 20 degrees (F) |
Temperature Rating (C) | -6 degrees (C) |
Weight | Short: 2 lbs. 4 oz. Short Wide: 2 lbs. 13 oz. Regular: 2 lbs. 11 oz. Regular Wide: 3 lbs. 5 oz. Long: 3 lbs. 1 oz. Long Wide: 3 lbs. 13 oz. |
Shell | 20-denier 100% recycled nylon ripstop |
Zipper Location | Left |
Insulation Type | Down |
Water-Resistant Down | Yes |
Fill | 650-fill-power duck PFAS-free hydrophobic down (RDS) |
Fill Weight | Short: 1 lb. 4 oz. Short Wide: 1 lb. 11 oz. Regular: 1 lb. 7 oz. Regular Wide: 2 lbs. Long: 1 lb. 10 oz. Long Wide: 2 lbs. 4 oz. |
Sleeping Capacity | 1-person |
Lining | 20-denier 100% recycled nylon ripstop |
Sleeping Bag Shape | Semirectangular |
Fits Up To (in.) | Short: 66 inches Short Wide: 66 inches Regular: 72 inches Regular Wide: 72 inches Long: 78 inches Long Wide: 78 inches |
Shoulder Girth (in.) | Short: 63 inches Short Wide: 75 inches Regular: 64 inches Regular Wide: 76 inches Long: 65 inches Long Wide: 77 inches |
Hip Girth (in.) | Short: 59 inches Short Wide: 73 inches Regular: 60 inches Regular Wide: 74 inches Long: 61 inches Long Wide: 75 inches |
Stuff Sack Size | Short: 18 x 6.5 inches Short Wide: 18 x 6.5 inches Regular: 20 x 7.5 inches Regular Wide: 20 x 7.5 inches Long: 20 x 7.5 inches Long Wide: 20 x 7.5 inches |
Stuff Sack Volume | Short: 9.8 liters Short Wide: 9.8 liters Regular: 14.5 liters Regular Wide: 14.5 liters Long: 14.5 liters Long Wide: 14.5 liters |
Compressed Volume | Short: 7.1 liters Short Wide: 7.6 liters Regular: 8.7 liters Regular Wide: 9.4 liters Long: 10.9 liters Long Wide: 10.1 liters |
Gender | Unisex |
Sustainability | Down certified to the Responsible Down Standard (RDS) Contains recycled materials |
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After trying out several bags for backpacking, aI finally got this one and am really happy with it. I went with the regular wide. I’m a plus size gal and I tend to toss and turn when I sleep, so every mummy bag I tried just felt way too claustrophobic. This is nice and spacious, even when it is zipped up to the mummy version. Of course with all that spaciousness, the bag takes up a bit more space when packed, but to be able to get a good night sleep makes it well worth it for me. I also love the little zippers at the front so you can be in the bag but have your arms out. Nice little touch so you can read while staying nice and cozy.
If you want a roomy, packable, down sleeping bag this is it. I don’t like mummy bags, I’m a big guy, they don’t work for me. I’ve had a lot of different bags over time but this one is by far the best. Vents and zippers move smoothly to find your comfort zone for both snug if you want, or vented and comfortable. Haven’t had it out in cold weather, but I’m confident the way it’s packed with down it will be fine down under 30 degrees. I spend about 30 nights a year around the country in tents, and have a closet full of pads/bags, and gear. This is my new go to bag for sure.
The first time I took this bag out camping it was 30°F and I woke up multiple times through the night absolutely freezing (wearing heavy wool base layers and socks) so I decided to wait till it warmed up a little more because I am a pretty cold sleeper and wanted to give it a fair chance. So I took it out camping when the coldest was going to be 36°F and I still woke up cold multiple times. I like this bag, I like it's versatility with all the zippers and vents, but the fact that it can't keep me warm at 36°F when it's rated for much colder than that is a huge turn off. I will be returning this bag.
I've only used this bag for 3 nights during a New Zealand hut trek in November so limited experience but so far I love it. In the hut I'd guess the temp was in the 40's (with approx. 30 bodies) b/c outside it snowed. I wore wool base layers to bed and was comfortable the whole time. I appreciate the venting for arms (didn't use much) and the flexbility to unzip lower part for more leg room (more comfortable for sideslipping and didn't need the extra coziness). Down Feels plush, not noisy fabric and beautiful aqua color. At 5'3" and slim I really appreciate the various size/weight options so I got the short; yay for not carrying extra unnecessary weight! The only thing I didn't love is that the head area wasn't big enough for my head resting on a small blow up backpack pillow. If it were really cold, I'd want my head inside the bag but in this case, it wasn't needed.
I loooove this bag. It is lightweight, comfortable, and super warm. I honestly feel like I would've been fine with a 30 degree bag because I mostly camp in the summer, but the big vent in the front and the arm holes make a big difference as far as cooling me off. Also. . . . . . the arm holes are super sweet. They make it so you can read a book or look at your phone before you go to bed. I've had a synthetic bag for years, and the feel and construction of this bag fell amazing. I don't backpack often anymore, but this bag is plenty light and comes with a compression sack to get it nice and small for packing. Would definitely recommend. Again, I love this bag.
Wow! I'm out of words. I've never been more excited to receive a piece of gear. The first time I unboxed The Boost I knew I'm getting more than just a sleeping bag, I'm getting a new friend. The customizable design is simply mind blowing. This is my first sleeping bag and I'm coming for Boost after returning a quilt from a different company. Quilt offered lots of weight savings but turned out to be a pain to use - it needed to be attached to the sleeping pad, it had an open back and no hood?! I'm going on my first backpacking trip with 30s F at night and I need sleeping system that will 1000% keep me warm. Quilt I picked just couldn't offer that and I can't take any chances. With The Boost I see exactly where every dollar went - every detail is high quality and thought through. It leaves me at peace that I will be warm at night and it will serve for years to come.
I bought this last month for a 3 night trip in GA. This bag is definitely my new go to. It's warm, comfortable, and the arm holes are elite. I'm a super warm sleeper and the arm holes served as great vents. I may or may not be using it to stay cozy now that I'm home. Excellent purchase.
This bag is FANTASTIC for anyone who feels restricted in regular-width bags (or side-sleepers, or those who "flail about"). The fabric is super-comfy against the skin and yet, seems durable. Looking forward to many years of use!!
I recently spent 5 days camping out, this bag was great , very comfortable to sleep in, warm and roomy for a side sleeper. I recommend it often at REI.