Comfort in the coldest places.

Marmot designed its Lithium 0-Degree Down Sleeping bag to deliver exceptional warmth and comfort, so you can spend restful nights in the alpine. The Lithium is part of Marmot's ultralight lineup, weighing just over two pounds, and 800-fill down gives it the compressibility needed to be a viable option during those more gear-intensive backcountry missions where every inch of pack space must be carefully considered.

The Lithium features newly redesigned baffle construction that uses a curved shape to help keep the water-resistant 800-fill down from wandering throughout the night. The foot box is anatomically shaped to give your toes some extra wiggle room and has a wrap-around construction to limit the amount of areas where heat can be lost as you sleep. Even though the down is coated with a Down Defender water-resistant coating, Marmot also used treated both the lining and Pertex Microlight face of the bag with a DWR finish for extra protection against moisture. Pertex Microlight fabric is also superlight and highly breathable, so it saves ounces and makes sure you don't sweat and wake up frozen in the middle of night.

  • 0-degree temperature rating
  • 800-fill down insulation
  • Down Defender water-resistant down
  • Mummy shape with anatomic footbox
  • Pertex Microlight 20D nylon with DWR finish
  • Full-length left- or right-handed zip closure
  • Second fold-down zipper
  • Curved wrap-around baffle construction
  • Reviews
  • Q & A

Not to Spec

  • Familiarity: I returned this product before using it

Ordered one. Returned it because the loft was nowhere near spec. Ordered another as thought the first was defective. Second one was just as bad and returning it as well. Not gonna try again. Too bad and very disappointed. The other reviews are positive, so I'd say order it; if it meets spec with regard to loft, it's a great deal. In general I've been very satisfied with Marmot gear; this one seems to have slipped through their quality control.


  • Familiarity: I've used it once or twice and have initial impressions

Bag is super warm and toasty. My wife used it while backpacking in the uintas and was very happy with how warm, comfortable and light it was.

All the warms

  • Familiarity: I've used it several times

Great sleeping bag for cold weather. You can also unzip it and get a leg out if you are in some warmer conditions. Packs down super small so it is easy to transport or put in a backpack. The hood enclosure is super snug with out being annoying. Pair this with a Nemo sleeping pad and you will have the best camp sleep you have ever had!

Stupendously Warm!

  • Familiarity: I've used it several times

I used to have a Marmot 30F bag and decided to take it out in winter months thinking I'll be fine car camping. Well... this is why I'm writing this review!
Needing a warmer bag, yet found this one that is completely inexpensive for the price and what you get. Let's be honest, as soon as I brought it home I took a fat nap because it was comfortable! They do say no-snag zipper... they say it works, I say it's impossible for a non-zipper snag. But that you cannot avoid, so this bag is absolute a recommended buy! Took this sleeping bag out to Jackson WY and it was perfect; no it was not in a car that time around. Slept comfortably with enough space, yet still be extremely warm! Worth the buy!

Best sleep I’ve ever had

  • Familiarity: I've used it several times

I just bought this sleeping bag this fall and just recently used it in northern Minnesota. I went on a 2 day backpacking trip and each night got below 10 degrees. What wasn’t good was that I woke up and everything was wet inside the tent. Everything except me anyways. The sleeping bag itself had condensation on the outside but I never got cold once. The bag kept all the moisture out and kept me warm all night. I would definitely recommend.

Stay warm

  • Familiarity: I've put it through the wringer

This sleeping bag is perfect for cold nights in the backcountry. I love the mummy shape layout, keeping you covered up nicely while providing enough room for a comfortable night sleep. Well designed, with full length zippers, and extremely durable.

What's not to like

  • Familiarity: I've used it once or twice and have initial impressions

This bag is so well made and designed, warm and one of the lightest 0° bags I could find, coming in at 2 lb 10 oz. You can see the attention to details in every aspect of this bag. The main zipper operates smoothly with a generous zipper tab and no snags. There's a small short zipper on the opposite side of the main zipper, this allows me to sleep with my arms outside the bag give me more room inside. I'm a big guy at 5' 11" 240lb and I wear a size 48 jacket so it's a little snug when all zipped up inside in my shoulder area, other than that it's very roomy for mummy bag. They even thought of putting little pockets at the end of the zipper run to tuck the zipper into keep the zipper off of any skin and
creating less drafts. There's a nifty little storage pocket on the inside of the bag perfect for keeping your phone or wallet in. You can snug the hood right down to a little tiny slot. Even the stitching seems to have quality everywhere you look, special little reinforcing tacks at stress points. Had this bag out in -1° weather I was warm and slept like a baby. Last I'd like to say inside this bag is really soft! This is a nice bag I like this bag. 😃

Just got another Marmot lithium sleeping bag had to get the long the regular was just too tight. The long fits me perfect I just needed a few extra inches to wiggle around in. Now I have three bags.

Awesome sleeping bag!

  • Familiarity: I've used it several times

I bought this for my son for Boy Scouts. We live in the North East. He recently camped out twice on two separate occasions in January and was very happy with the warmth of the bag. It got as low as 15 and he said he was totally warm. He is not a big kid. I am extremely happy with this bag and the customer service at Backcountry! Love it