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You'll be cozy and comfy; pack earplugs.

Your trekking buddy's balloon-like synthetic sleeping bag fills his whole backpack; your Sea To Summit Trek TkI 32 Degree Down Sleeping Bag compresses down to the size of three water bottles, so you have room for the essentials plus a few souvenirs. It's stuffed with lofty, moisture-resistant Ultra-Dry Down 650+ and sheltered with breathable, weather-repelling 2D Perma Shell, so when the going gets cold or damp your bag won't wilt or freeze. And a cushioned hood, draft tube, and tapered rectangular shape will keep you so cozy you'll sleep like a baby. Now only if your partner would stop whimpering.

  • Comfy in chilly moderate weather, with a 32F lower EN rating and 41F comfort rating, you’ll stay warm on high-altitude summer treks, or late spring or early fall camping trips
  • Almost-magical Ultra-Dry Down 650+ goose down repels moisture, retains loft, dries quickly, and fights bacteria and microbial growth for dry, fresh comfort
  • Differential-cut tapered rectangular shell with 3D side walls, 60/40 fill-ratio, and side block baffle gives wiggle room with lean-fit warmth
  • Regular length comfortably accommodates a person six feet tall; long length fits someone six-foot-eight
  • High-density, downproof 2D Perma Shell 33D nylon weave with DWR finish repels water at its durable exterior and condensation on the inside to keep you dry
  • Super-soft, downproof lining breathes and feels luxurious next to skin for all-night comfort
  • Cushioned internal hood drawcord with dual adjustment hugs your head with downy warmth
  • Two-way zips with separate foot zip let you convert bag to duvet for indoor or warm-weather use
  • Zip draft tube with anti-snag seals out the cold for optimal cozy comfort
  • Weighs a mere 1lb 13oz (regular) or 2lb 2oz (long) for easy portability
  • Compresses in bag from 10 liters to 3.3 liters, so you’ll have room in your pack for other things
  • Oversized internal zippered pocket secures traveling essentials at your side
  • Includes Ultra-Sil compression stuff sack, mesh storage bag, and laundry bag for easy maintenance and convenience

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Here's what others have to say...


Great bag!

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

I bought this bag last week. received it 2 days later with the free 2 day shipping. I cant even begin to say how awesome that was! I used this in the sequoias this weekend. the temp got down to the low 20's and was a little worried it might not be enough. I slept in thermals a light jacket wool socks and a beanie and a Nalgene bottle of hot water at my feet. you can feel cold spots at the feet but I expected that and it was a trade off I was willing to make to have the extra room in the leg/feet area. I ended up having to take the jacket off during the night and was still nice and warm and never had to close the hood. the material has a nice feel to it and seems sturdy. it does take some time to get it into the stuff sack but when you do it compresses to about the size of a football if you want. or if you are car camping you can just throw it in the storage bag. the 2 separate zippers is the only thing i am not a fan of. I kind of wish it was just a full length zipper. but it is nice to have the option to open to adjust the airflow. It is not the lightest bag i saw but for the price ($215 for the long) ill happily deal with the little extra weight. it is perfect for what i wanted it for and look forward to many more trips with it! i will update if anything changes after the next few trips. thank you for the great price and the great product!

Unanswered Question

Which sleeping bag liner would go best...

Which sleeping bag liner would go best with this bag since it is not a traditional mummy shape?