Marmot Atom 40 Degree Sleeping Bag


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Marmot Atom 40 Degree Sleeping Bag

The Atom's ultra-light design and our highest quality down have given it cult status among alpinists as a bivvy bag on extreme climbs, but its comfortable, silky fabric make it a great bag for warm-weather bivvies on casual summer road trips as well.

  • Main Material: LightForce 1.2 oz 100% Nylon Ripstop DWR
  • Lining Material: LightForce 1.0 oz 100% Polyester Taffeta DWR
  • Insulation Material: 850+ Goose Down
  • Certified 850+ Fill Goose Down
  • Classic Trapezoidal Foot Box
  • EN Tested
  • Filled and Finished in Santa Rosa, California
  • Full-length Zipper
  • Hood Draw Cord
  • Insulated Draft Tube
  • Nautilus 6-Baffle Hood
  • Sewn-Through Baffles
  • Stretch Tricot Baffles at Hood and Foot Box
  • Stuff and Storage Sack Included
  • Velcro®-free Face Muff
  • Zipper Guards
  • Stature: 72in / 183 cm
  • Shoulder Girth: 62in / 157 cm
  • Hip Width: 58in / 147 cm
  • Foot Box Width: 40in / 102cm
  • Weight: 1 lb 5 ozs / 595 g

Purchase the Marmot Atom 40 Degree Sleeping Bag from All order totals over $45 qualify for free ground shipping.

5 Star Rating


5 Stars SteGonz - May 1 2011

The Marmot Atom Sleeping Bag is perfect for 3 season backpacking. It is highly compressible and hardly noticeable in my pack. It is rather warm for a 40, but don't use it in temps below 32 degrees. The pros for this product are the size, warmth to weigth, and Marmot quality. The only con I can find is the outer fabric seems like it could tear easily and the price(try to get it on sale).

5 Stars Goonies - April 3 2011

Great Sleeping Bag!
The Marmot Atom is a superbly crafted bag in which every detail was thoughtfully considered. The inner and outer materials are super soft and smooth, there is enough room to move around inside (I'm 5'8'' & 165 lbs.), and plenty of foot room. The zipper mechanism itself is made of a very light metal and never catches in the bag fabric due to the special lining near the zipper teeth. This sleeping bag is incredibly light. I've used the Atom in temperatures as low as the low 50s wearing only boxers and a t-shirt and had to sleep with the bag completely unzipped (NOTE: this bag was used with a sleeping pad that had an R-value of 3.8). I backpack Spring through Fall and feel this bag will comfortably see me through most of the Midwestern U.S. temperatures I might experience. The only slight concern I have regarding this bag is that the thin and soft material seems like it may not be the most durable, but so far it has held up to all my uses just fine. The bag is quite small when it's in the stuff sack, but is capable of being compressed further to roughly half the height of that shown in the accompanying picture.

5 Stars Trent Sherman - November 10 2010

Wise Choice
The Marmot Atom sleeping bag is a must have for summer trips that require an extra light load. The bag is small, extremely lightweight and its quality is what you come to expect from Marmot. Again, Altrec came through with a great product at a reasonable price.

5 Stars Shopper - January 12 2010

The perfect bag.
Bought this bag after agonizing over the price. Glad that I did, it is amazingly warm for the weight and compacts down to about the size of nalgene with very little effort. I sleep warm and tried this bag in 30ish degrees and was warm with some boxers, t-shirt and socks. I will say that the regular length for me (6') was just long enough. The full length zipper is great for venting when it is warmer out. Also, it seems you could move more of the down to the top of the bag to make it warmer since the down you lay on compresses and loses its loft. The only downside I see to this bag is my girlfriend likes it so much I might have to buy another one for her :)

5 Stars Shopper - December 9 2009

Great and lightweight
This is a great sleeping bag, lightweight and warm enough for me :) A smaller stuff sack would be great since the bag stuffs really small!

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