Free 2-Day Shipping on Orders Over $50* - Limited Time Only

Take 20% off one full-price item

Restrictions Apply >
Use Code: SPRING20


Just so we're all clear, Helium is lighter than air.

If helium's good enough for balloons, it's good enough for you. That's the theory behind Marmot's Helium 15-Degree Down Sleeping Bag, which, though it isn't actually filled with lighter-than-air gas, still weighs a miraculous two pounds, putting it squarely in the "ultralight" category. You can't make a bag that light and warm by mistake, and it's clear Marmot put some serious work into the Helium―it's filled with super-lofty 850-fill goose down, and the Pertex Microlight fabric is ultralight and treated with a DWR coating to repel water and keep your bag warm through spring, summer, and fall. 

The down's high-tech, too, seeing as it's been treated with Down Defender, a water-repellent technology that helps it maintain loft even if some water sneaks through the shell. Cold air won't be able to get near you either, thanks to the Helium's insulated collar, draft tube, and six-baffle Nautilus hood that seals around your face to keep all your hard-earned warmth from escaping into the night. There are stretchy tricot baffles around the head and feet, too, to give you a little extra space without the need for extra material and weight.

  • 15-degree lower limit rating, 28-degree comfort rating
  • 850-fill down with Down Defender water-resistant treatment
  • Mummy bag with sewn-through baffles
  • Pertex Microlight nylon ripstop fabric with DWR treatment
  • Ultralight
  • Six-baffle Nautilus drawcord hood with insulated collar and draft tube
  • Trapezoidal footbox construction
  • Stretch tricot baffles and head and foot
  • Stuff and storage sack included
  • Filled and finished in the USA

Share your thoughts

What do you think of the

Marmot Helium Sleeping Bag: 15 Degree Down

? Share a...

Write a review

No file chosen

Rather attach a photo from another website?

Rather attach a photo from your computer?

    Add a:
  • Share a photo
  • Share a video


Only jpg, jpeg, png, gif or bmp files please.

Submit Cancel
Now review from the App. Download

Here's what others have to say...

5 5

Stays Lofty 10-Times Longer

  • Familiarity: I've put it through the wringer

The Marmot Helium weighs just over two pounds, packs down small, has a silky smooth shell fabric, and all of that is great for backpacking, but my favorite thing about this bag is the Down Defender treatment. The treatment makes the down water-resistant, and that means it will maintain its loft for 10-times longer than untreated down. Remember that loft is practically synonymous with warmth, so this is a big deal, especially on multi-day trips.

Stays Lofty 10-Times Longer
2 5

Too short!

  • Gender: Male
  • Familiarity: I've used it several times

Very nice bag, but too darned short! I'm 5'9" and the regular size should go to 6'. It's a squeeze for me to get into this bag completely zipped up. I feel like my feet are scrunched in the bottom or head is scrunched in the hood. Marmot must have trimmed some length to loose some weight. Check the length!

5 5

Solid all around bag

  • Familiarity: I've used it several times

I bought a previous season's model on clearance and have used it on a number of warm and cold weather backpacking trips. The weight and stuff size are great, but for the full retail price you could do better. The stuff sack that came with the bag is a tad small (the bag actually pushes open the draw string), but I've found it fits perfectly in a 10L dry bag.

With an insulated sleeping pad and a down jacket this bag kept me warm at 0-10 degrees, but I don't get too hot on warm summer nights either. I would say the temp rating is accurate/conservative.

The only complaint I have is that the zipper is cheap and hard to use for a bag in this price range. It doesn't catch on the bag material, but it doesn't zip as well as you'd expect it to.

Bottom line: If you can get this bag on sale, buy it and it won't disappoint. But for $400, consider looking elsewhere (zpacks, featheredfriends, etc)