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Sea to Summit Trek Tk I Sleeping Bag


    Sea to Summit Trek Tk I Sleeping Bag

    The lightweight Sea to Summit Trek TkI down sleeping bag keeps you warm in a broad range of environments and activities, whether you're tramping in New Zealand or road-tripping across the States. See details

    • $249.00 - $269.00

    Item # 830938

    The lightweight Sea to Summit Trek TkI down sleeping bag keeps you warm in a broad range of environments and activities, whether you're tramping in New Zealand or road-tripping across the States.

    Product size and color
    * Color/Size is out of stock but can be backordered.

    The lightweight Sea to Summit Trek TkI down sleeping bag keeps you warm in a broad range of environments and activities, whether you're tramping in New Zealand or road-tripping across the States.

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    The lightweight Sea to Summit Trek TkI down sleeping bag keeps you warm in a broad range of environments and activities, whether you're tramping in New Zealand or road-tripping across the States.

    • Insulated with high-loft 650-fill-power duck down for warmth, light weight and compressibility; Ultra-Dry Down™ water-repellent treatment protects down from moisture
    • Ultra-Dry Down is a water-repellent polymer treatment applied to the 650-fill down; Ultra-Dry Down retains 60% more loft and absorbs 30% less moisture than untreated down
    • With a European Norm (EN) lower-limit rating of 32°F, the TkII bag will help keep you warm in mild weather
    • Shell fabric is constructed of 2D PermaShell™ technology, a high-density weave, 33-denier fabric treated with a Durable Water Repellent finish
    • Shell material is highly vapor permeable and downproof
    • Lining is a breathable, durable 40-denier nylon fabric with a soft touch
    • Full-length side zipper and foot zipper allow bag to be converted from sleeping bag to a duvet/down comforter; this also allows 2 Sea to Summit bags to be zipped together
    • Oversize draft tube backing the 2-way zipper keeps the warmth in and the cold out; zipper is backed by stiff, antisnag tape for smooth operation
    • Semirectangular shape provides more room than a mummy bag for a more comfortable sleeping bag while maintaining thermal efficiency
    • 2-dimensional hood features drawcord adjustment to cinch and tighten around head; hood is designed to open flat when sleeping bag is used as a duvet/down comforter;
    • Differentially cut inner layer is smaller than the outer layer to create a consistent thickness of insulation that precludes cold spots
    • Large zippered interior secuity pocket is great for stowing a few essentials, alleviating middle-of-the-night fumbling and preserving battery performance in cold weather
    • Baffle construction allows the down to remain fully lofted and keeps it from shifting
    • Sea to Summit Trek TkI bag comes with a Ultra-Sil® compression sack, an oversized mesh storage cell and a large cotton sack
    • European Norm (EN) is an independent third-party temperature rating, allowing accurate comparisons across brands with other EN-rated bags


    Item 830938

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    View specs for sizes: Long Left, Regular Left

    Sea to Summit Trek Tk I Sleeping Bag Specs
    Long LeftRegular Left
    Best use
    32 degrees Fahrenheit32 degrees Fahrenheit
    41 degrees Fahrenheit41 degrees Fahrenheit
    32 degrees Fahrenheit32 degrees Fahrenheit
    0 degrees Celsius0 degrees Celsius
    2 lbs. 2 oz.1 lb. 13 oz.
    0.9 kilograms0.8 kilograms
    650-fill duck down650-fill duck down
    14 ounces12 ounces
    78 inches72 inches
    61 inches60 inches
    60 inches59 inches
    7.5 x 14 inches7.5 x 14 inches
    10 liters10 liters
    5.5 liters5.1 liters
    EN lower limit (rating for men)
    EN comfort (rating for women)
    Temperature rating (F)
    Temperature rating (C)
    Weight - metric
    Insulation type
    Water-resistant down
    Fill weight
    Sleeping bag shape
    Fits up to (in.)
    Shoulder girth (in.)
    Hip girth (in.)
    Stuff sack size
    Stuff sack volume
    Compressed volume

    Sea to Summit Trek Tk I Sleeping Bag

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    Sea to Summit Trek Tk I Sleeping Bag is rated 4.5 out of 5 by 6.
    Rated 5 out of 5 by from Perfect for folks afraid of mummies My first mummy bag, and I was really pleased with it on its first outing in 37 F weather. I'm a spread-eagle sleeper, and mummy bags are too confining to me. However, I needed a really small, lightweight bag for backpacking. I compared dozens of bags and picked this one because it appeared to be wider in the footwell, have a wider top so I can put my elbows out, and is quite light weight. The footwell is a perfect compromise between typical mummy bags and a rectangular bag. I had enough room to not feel cramped. The top has a wide opening, and lays flat--perfect for spread-eagle elbows--but it cinches up nice to make a warm halo. I know super-light-weight gear can tend to have wimpy zippers, but this one seems good to me. Had no snag troubles. Time will tell. Temperature performance was great in 37 F (thermals, an extra t-shirt, thick socks). We'll see how breathable it is during the summer hikes, but I'm expecting it to be fine. I think this was the highest-priced bag I considered, but the room, the light weight, and the 3 bags it comes with (cinch, stuff, washing) help the overall value.
    Date published: 2014-03-26
    Rated 5 out of 5 by from Great Summer Sleeping Bag! Great bag, I was toasty warm on all my summer trips thus far (never got below 40degrees). The zipper on this bag really doesn't catch which is a problem I have on all my other bags. Also there is a separate zipper for your feet so you can vent just at the bottom. The bag is very roomy, which is surprising since it is so lightweight and packs down so small, it is bigger than the foot print of my thermarest!
    Date published: 2014-04-08
    Rated 4 out of 5 by from Great, Warm, Diverse Sleeping bag The Sea-to-Summit worked well in 35 degree windy weather. I was a little cool in the night from the ground, but considering I didn't bring a sleeping pad, the sleeping bag worked pretty well. The hood closed well to keep my head warm during the night as well during the windy nights. I wouldn't take this sleeping bag much below freezing temperatures, but it worked well for the situation I was in.
    Date published: 2014-03-26
    Rated 4 out of 5 by from You can't beat this bag...kinda.... Getting the bad out of the way: This bag is clammy, especially in the foot box. Using this bag in an open-air cabin with 30mph gusts of winds, I had to keep the top half of this bag unzipped. I feel this bag relies less on its down fill and more on the material to achieve its 32 degree rating. I would wake up hot and open up the bag. Then wake up cold and have to close it up. And the zipper does snag a little bit. Not as bad as other bags. Just get used to it. It will always happen no matter what bag you have. Onto the good: This bag packs down really small. It fits in the Sea To Summit XS compression sacks with enough room to fit lightweight PJs. Its fairly lightweight too. The hood is great except for one thing: No face muffler. The hood opens flat so you can put your pillow in it and pull up the draw cords to keep it in place throughout the night. And lets face it, you only use your hood in extreme weather right? The fully openable feature is essential. This allows for good ventilation. After fussing around with it, I found the sweet spot: Open the side bottom to about thigh high. Then open foot box (Opposite side from open zipper) about 4 inches. This kept me more comfortable than before but still not perfect. I use this for work and it keeps me warm enough and comfortable enough in the tent or cabin. Traveling with this bag would put it to its best use. Folds open so you can use it like a comforter and in this position it is extremely comfortable. I haven't put it to extreme tests so I'm not sure how it would handle tough spots but based on Sea To Summit's amazing performance in the past (I own the xTI and a few other products. They are amazing) I would bet on it to deliver the goods. Final word: Although this bag doesn't do it all perfectly, there's nothing out there that does it better for the size/weight/accoutrements/$$$$$$$. Add a muffler and a bit more breathability and 5 stars all the way. Thanks for another great product S2S!!
    Date published: 2014-03-26
    Rated 5 out of 5 by from The Right Bag Used this bag this spring in Maine and it was Perfict, alot better than the -20 bag I had been using. Tryed it with a poncho liner then just by its self and liked it that way best (no liner)
    Date published: 2014-03-21
    Rated 4 out of 5 by from It's fine It's got a zipper at the foot which i don't need. The zippers overlap, but occassionally I must bump it or fail to close it all the way, and it opens an inch, and I can feel my feet geting cold. It's a feature I don't need, but maybe desirable to others to keep feet ventilated and dry. Rated for 32 deg F. I would say that's accurate. Used it in 30 deg F weather with 65% humidity. I was warm, although i did sleep in about two layers plus toboggan and gloves, and nalgene bottle filled with hot water in ziplock bag. It'll pack down to less than football size, but I don't want to crush the feathers. I don't need the space so i only lightly compress it. Comes with fancy washing bag, and long term storage bag. Face hole cinches with a draw cord. Works well enough. Bag always fluffs out fully after I roll it out.. I like it. Perhaps wish I got a bag with a few more ounces of feathers, to hold the heat even better. I'm thin, and could use the extra insulation. But I like the lightweightness of this bag. Net weight is accurate. Am pleased with the bag.
    Date published: 2014-03-21

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