photo: Marmot Helium MemBrain 3-season down sleeping bag


Regular Long
Price MSRP: $459.00
Historic Range: $374.95-$488.95
Reviewers Paid: $350.00-$367.00
Weight 2 lb 5 oz / 1050 g 2 lb 9 oz / 1162 g
Fill Weight 1 lb 3.5 oz / 552 g 1 lb 5.5 oz / 609 g
Temperature Rating 15 F / -9.4 C 15 F / -9.4 C
EN Comfort 22.5 F / -3.6 C 22.5 F / -3.6 C
EN Lower Limit 13.8 F / -10.1 C 13.8 F / -10.1 C
EN Extreme -19.8 F / -28.8 C -19.8 F / -28.8 C
Fill 850 Fill-Power Down 850 Fill-Power Down
Shape Mummy Mummy
Max User Height 6 ft 0 in / 180 cm 6 ft 6 in / 200 cm
Hip Girth 58 in / 147 cm 58 in / 147 cm
Foot Girth 40 in / 101 cm 40 in / 101 cm
Price $459.00 USD $479.00 USD


This thing is like a dream. Waterproof outside, breathable…

Rating: rated 5 of 5 stars
Price Paid: $367

This thing is like a dream. Waterproof outside, breathable and comfortable inside. The MemBrain lining, although I'm not sure if it's worth the extra money, feels amazing.  

After camping while smelly and sweaty, this bag seems to remain clean, which means you'll have to wash it less and it'll last longer than other bags. The down is very lofty and lightweight, like sleeping in a warm cloud, and packs down very small.  

Quality seams and no leakage; I was worried at first as I saw some down on the bag when it arrived but it must have been from the factory since I haven't seen any since.

I'm 6'0" average build and got the long version and it fits great. I find that even though most regular bags supposedly fit 6ft people, the hood won't cover your head enough.  Found at with a 20% off coupon for $367 ($430 normally at many of the cheapest places).

Great lightweight 3-season backpacking bag. Have been…

Rating: rated 5 of 5 stars
Source: bought it new
Price Paid: around $350 on sale


Great lightweight 3-season backpacking bag.


  • warm
  • roomy
  • lightweight


  • none

Have been down in the mid twenties with no extra clothes on, very warm, very roomy mummy shape. I'm 5'9" 200 lbs with plenty of room, packs down small. At a shade over 2 lbs great bag for backpacking.

Have had the bag for about 4 yrs with no problems at all. Thanks.

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