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Sea to Summit Trek TkII Sleeping Bag

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    Sea to Summit Trek TkII Sleeping Bag

    Pack this lightweight Sea to Summit Trek TkII down sleeping bag for your next hostel trip through Europe or backpacking in South America. It keeps you warm in a broad range of environments!

    • $279.00 - $299.00

    Item # 830941

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    * Color/Size is out of stock but can be backordered.
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    • Insulated with 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 18°F, the TkII bag will help keep you warm on spring, summer and fall backpacking trips
    • Shell fabric is constructed of 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 traditional sleeping bag to a duvet/down comforter
    • Semirectangular shape provides more room than a mummy bag for a more comfortable sleeping bag while maintaining thermal efficiency
    • Differentially cut inner layer is smaller than the outer layer to create a consistent thickness of insulation that precludes cold spots
    • 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
    • Large interior secuity pocket is great for stowing a few essentials, alleviating middle-of-the-night fumbling
    • Baffle construction allows the goose down to remain fully lofted and keeps it from shifting
    • Sea to Summit Trek TkII 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 830941

    REI Membership

    View specs for sizes: Long Left, Regular Left

    Sea to Summit Trek TkII Sleeping Bag Specs
    Long LeftRegular Left
    Best use
    18 degrees Fahrenheit18 degrees Fahrenheit
    30 degrees Fahrenheit30 degrees Fahrenheit
    18 degrees Fahrenheit18 degrees Fahrenheit
    -8 degrees Celsius-8 degrees Celsius
    2 lbs. 7 oz.2 lbs. 4 oz.
    1.1 kilograms1.0 kilograms
    650-fill duck down650-fill duck down
    19.4 ounces17.6 ounces
    78 inches72 inches
    61 inches60 inches
    60 inches59 inches
    7.5 x 14 inches7.5 x 14 inches
    10 liters10 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 TkII Sleeping Bag

    Loading Ratings & Reviews...

    Rated 4.1/5 based on 10 reviews
    Rated 1out of5
    by fromNot up to par They had the right idea, which is why I bought it once and then gave a second one a try. Both were missing down, first in the upper chest baffle, second in the head. Making this bag completely useless in my book. Sent both back. First shot at Western Mountaineering did the trick. Anything but Sea to Summit for a sleeping bag, until they get it together.
    Date published: 2012-06-26
    Rated 4out of5
    by fromVery comfortable. Compacts well and is lightweight for backpacking. Great comfy bag to get into after a long day on the trail. Pretty warm. I get very cold when I sleep and can't stand being confined in the top of the bag so I leave the top unzipped and wear a fleece. Given that, it keeps me decently warm. My husband has the same bag and cocoons himself and is very warm.
    Date published: 2014-06-09
    Rated 5out of5
    by fromUntested Review I ordered two of these and received them several days ago. I did have concerns about the down distribution prior to receiving them. However, the two I received have no issues whatsoever. Granted, I have not used them in the elements as of yet. But I have no reason to doubt their performance as any possible imperfections/flaws that others have noted are not present. Basically, if they hold to their temp rating, which I suspect they will, then I would suggest grabbing these up. Overall, these are of great quality , and the considerations that went into their design are impressive.
    Date published: 2013-09-05
    Rated 5out of5
    by fromVery Nice Bag I researched dozens of sleeping bags and always ended up liking the TKII the most. I had five requirements for a new bag: (1) down filled, (2) warm in 30+ degree temps (bag is rated 18 degrees), (3) reasonably price, (4) not heavy/bulky, and (5) not a mummy style. I can't stand the thoughts of being cramped in a mummy bag and the Trek bag solves that issue with a larger foot area. The bag has a very comfortable lining, and of course, as with most down filled bags, the feel of the bag around you is naturally cushiony. The zippers open and close with ease. I didn't encounter any snagging but we all know that is possible with most sleeping bag zippers. The side zipper goes down to the foot area and the foot area has a separate zipper if you want to air your feet on a warm night. Before I purchased the bag from REI, I contacted Sea to Summit and inquired about one of the previous customer reviews about the bag missing down. S2S stated that the issue had been resolved and they had no complaints since then. The down in the bag I received was evenly distributed. I also did a moisture test and my bag's lining did not absorb any of the water I placed onto it. The water beaded and rolled off like mercury. Now, it may absorb water if left in contact with water for a long time, but over the course of one minute, I saw no water absorption. The newer TREK models have the Ultra-Dry down. I was concerned I may receive the older model, but REI (thank you) shipped the latest model. As of this review, I don't think the description states the bag containing Ultra-Dry down. I'm pleased with the purchase and recommend it to anyone who is looking for something within the five requirements listed above. NOTE: It comes with a storage bag, laundry bag and a compression sack :)
    Date published: 2013-04-16
    Rated 3out of5
    by fromDown Is Not Evenly Distributed First of all, I think this bag has an amazing design. I like the semi-rectangular cut. When I first opened the bag, it was light and fluffy. I used it as a down comforter for 2 nights. It's the second Sea To Summit bag that I have purchased. I returned the first one because the zipper was stitched unevenly in 1 place. This concerned me about the quality control of the bag. I ordered another from REI and the bag looked beautiful. It also came with the new moisture resistant down. I packed it tight in the compression sack and loaded it into the car for a back packing trip in the Sierras. We had warm weather that rarely dipped below 50 degrees, yet I got cold. I was sleeping on a down insulated mat too, so I concluded the bag was more than likely the problemm. After inspecting the bag, I noticed that it was flat or missing down in several areas. I have read other reviews that stated similar problems. I contacted Sea To Summit and the rep appeared to be shocked. They have excellent customer service and will bend over backwards to help you out. After using the bag for 6 nights, I am returning it and will order another as I am very hopeful of this product. The design and comfort of the bag is very close to another down bag that I have been using for 25 years and sells for $500. That down bag has been retired as it's seen better days.
    Date published: 2013-09-02
    Rated 4out of5
    by fromGreat sleeping bag I bought this bag because of the lab verified temperature rating, the semi-rectangle shape, and its weight. The bag meets or exceeds every expectation I had for it. It is warm, it is light, it easily packs down to nearly nothing. In addition to the compression sack, the company included a storage bag (that keeps the bag secure but not compressed) and a laundry bag (if you decide you must wash it). The semi-rectangle shape is very roomy. Even at my not insignificant 5'11, 225 build I could turn over easily in this bag.
    Date published: 2012-07-16
    Rated 4out of5
    by fromGreat first attempt I used the Trek II this summer hiking the Oregon PCT. About 250 miles and it's holding up rather well; a grand total of one leaked down. Zipper is top notch with a nod to the ability to fully unzip...makes for a nice comforter-style blanket that's large enough to share. The bag is ultra roomy without being overly heavy, something I thoroughly enjoyed as the mummy style for me is a bit too claustro. Never really tested the lower bound of the temperature rating, but I would never have noticed the freeze on a night camped above 7000ft if it weren't for the puddles. I'm right at 6' so the long seemed to be the logical choice. It fits well without too much room in the foot to keep my feet from warming up. The shell did take a little moisture at the foot on some rainy nights when rubbing against the tent wall, though it didn't seem to effect the performance of the bag. Most other places seemed to bead and repel water readily.
    Date published: 2012-10-10
    Rated 5out of5
    by fromHappy with this bag I am very happy with this bag, I don't do well with mummy style bags and need the extra room of a semi-rec and this one features a lot but also packs down nicely and is good on it's weight and has a decent tempature rating that can take one into the warmer part of winter. There were also other reviews about the shell absorbing moisture, I have not noticed that as I spilt some water out of the jetboil onto my bag/pad and the water ran off the bag, it did not get absorbed.
    Date published: 2012-10-24

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