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  • Sea To Summit - Trek TkII Sleeping Bag: 18 Degree Down - One Color

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  • Sea To Summit - Trek TkII Sleeping Bag: 18 Degree Down - One Color

Sea To Summit Trek TkII Sleeping Bag: 18 Degree Down


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    6 Reviews


    Like the most gracious host: warm and incredibly accommodating.

    The Sea To Summit Trek TkII 18 Degree Down Sleeping Bag combines the roomy comfort of a recreational setup with the high-tech features of an alpine bag. The classic, tapered rectangular shape holds heat close to your body without the restriction of a mummy, and the cushioned hood employs double drawcord adjusters for head-hugging comfort. When things heat up, open the side and separate foot zip and use as a real duvet, not an awkward V-shaped coverup.

    • Comfy in chilly moderate weather, with an 18F EN lower limit rating, you’ll stay warm on three-season treks
    • Almost-magical Ultra-Dry Down 650+ goose down repels moisture, retains loft, dries quickly, and fights 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
    • Short length comfortably accommodates a person five-foot-five; regular length, a person six feet tall; long length extends to fit someone six-foot-eight
    • Breathable, 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 2lb 3oz (short), 2lb 4oz (regular), or 2lb 7oz (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 stuff sack and mesh storage cell and laundry bag for easy maintenance and convenience
    • Item #STS0175

    Tech Specs

    2D PermaShell (33D nylon)
    650-fill Ultra-Dry Down (85% duck down, 15% feathers)
    DWR coating
    Draft Collar
    Max User Height
    [short] 5 ft 5 in, [regular] 6 ft, [long] 6 ft 7 in
    Shoulder Circumference
    [short] 59.05 in, [regular] 59.84 in, [long] 61.42 in
    Hip Circumference
    [short] 58.27 in, [regular] 59.05 in, [long] 59.84 in
    Foot Circumference
    [short] 39.37 in, [regular] 39.76 in, [long] 40.16 in
    Stuff Size
    10 - 3.3 L
    Stuff Sack
    Storage Sack
    15 F
    European Norm Comfort Rating
    30 F
    European Norm Lower Limit Rating
    18 F
    [short] 2 lb 3 oz, [regular] 2 lb 4 oz, [long] 2 lb 7 oz
    Recommended Use
    camping, backpacking, travel
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

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    • Familiarity: I've used it several times

    I have owned quite a few bags and this bag is without a doubt my favorite. I had read many reviews and the complaints but i have to disagree with them all. This bag is soft, the loft is excellent, and its roomy. The zipper system is fantastic and work flawlessly 99.9% of the time. The hood cinches comfortably around the head and face and is easily adjustable with a simple draw string. I'm mostly a summer camper in the PNW and its a bit warm for that honestly so i just purchased the Trek TK I also =) Go get one! You'll love it!

    Versatile 3-season Bag

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

    I took this bag out recently for a camping trip. I tested at temperatures between 45 and 30 degrees F using an insulated pad and 3-season tent.

    The bag is light and packs down small enough for most backpacking needs, about 10" x 8" in the compression sack. Not the smallest but pretty good for a tapered-rectangular shape bag. A compression sack, stuff sack and mesh bag are included.

    This bag is roomy, plenty of space throughout and a very wide hood when uncinched. If you are a side sleeper rejoice, no more waking up in a straight jacket. The toe-box has a separate zipper which can be opened as ventilation or as a means to completely unzip the bag, transforming it into a down blanket. I think this is a great feature which expands the temperature range and versatility. Having a down blanket for summer camping in my hammock? yep. However, I found that the bag does just an adequate job keeping you warm in colder temps. The trade-off for a roomier bag like this one is more volume to keep warm. The bag's extra space which felt great at 40 degrees created cool spots at 30F. If you have a larger frame this bag could fit the bill, but @ 5'11" and 160lbs I found myself on the cooler side of comfortable at 30F. Nothing against the bag construction, just a matter of fit in my opinion.

    Overall a great 3-season bag that emphasizes spaciousness and versatility. Just be mindful that if you sleep cold or are smaller-sized you should add a few degrees to the temp ratings here.

    Trek II and AT Thru-Hike 2014

    • Familiarity: I've put it through the wringer

    I purchased a Sea to Summit Trek II sleeping bag to use on my 2014 Appalachian Trail Thru-Hike. It is the first high end sleeping bag I have owned. I was concerned about a straight out mummy bag, found the Sea to Summit Trek II and it fit the bill perfectly. Plenty of room in the hip and knee area and you can turn inside the bag without the bag following you.(I had a Long) In hot weather I used the Trek II as a quilt and in cold weather I zipped the Trek II up and used as a conventional bag. the bag weathered daily use from April 6 - September 14, 2014 when we reached the top of Katahdin without issue or any substantial wear. There are lighter bags but you loose room. I loved the bag and will use a Trek II on my next long distance hike. Very well made.

    Trek II and AT Thru-Hike 2014

    Down to the rescue

    • Familiarity: I gave it as a gift but have feedback to share

    I gave this as a gift, but thought about taking it for myself when I got it. This bag is what you dream of, just over 2 lbs for longer backpacking adventures with 650-fill duck down to keep you cozy at night. The sizing on this is definitely correct as well as the temperature rating as the conditions that it has been used in reached about 20 degrees F comfortably. It also comes with a stuff sack, mesh storage bag, and laundry bag, allowing you to pick and choose what is the best way to store and carry the bag. The storage sack is particularly nice to have a good way to store the bag when you aren't on the trail to keep from compressing the down too much. Finally, the DWR coating on the bag is an added benefit as well. With the major downside to down insulation being that it functions so poorly when wet, having that DWR coating is a comforting feature. A great bag to look into for 3 season camping!

    Wonderful bag

    • Familiarity: I've put it through the wringer

    It compresses small, it's very warm, it's roomy, you can open the hood to allow for more air if it's too hot in the bag. The footbox can unzip if you are too warm. The whole thing can be a blanket. It's an excellent bag and I've slept in it down to 9 degrees. There are also loops for hooking it on to a sleeping pad so you don't roll off.