The Sea to Summit Trek Tk II is a lightweight, 3-season bag with a roomy semirectangular shape and high-loft water-resistant down insulation for excellent warmth and compressibility.
Fill
650-fill duck down
Temperature Rating (F)
18 degrees (F)
- 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 Tk II 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 (DWR) 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 security 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 Tk II bag comes with a Ultra-Sil® compression sack and a mesh storage sack that can be used for drying the sleeping bag in a dryer
Imported.
Temperature ratings are intended as a guideline to help you compare products, rather than a guarantee of warmth, since many different factors contribute to your comfort while you sleep. Backpacking bags are typically rated for temperature according to an independent testing protocol—currently International Organization for Standardization (ISO) 23537, though some older items followed European Norm (EN) 13537. Testing is based on a person wearing one base layer and a pair of socks, sleeping on an insulated surface with a minimum R-value of 5.38.
Each bag then gets 2 ratings: the Comfort rating is the lowest temperature at which the bag will keep the average "cold sleeper" comfortable, and the Lower Limit rating is the lowest temperature at which the bag will keep the average "warm sleeper" comfortable. Some brands determine their own temperature rating by aligning to the Comfort rating for women’s bags, to the Lower Limit rating for men’s bags, or somewhere in the middle for nongendered bags.
View all Sea to Summit Backpacking Sleeping BagsEach bag then gets 2 ratings: the Comfort rating is the lowest temperature at which the bag will keep the average "cold sleeper" comfortable, and the Lower Limit rating is the lowest temperature at which the bag will keep the average "warm sleeper" comfortable. Some brands determine their own temperature rating by aligning to the Comfort rating for women’s bags, to the Lower Limit rating for men’s bags, or somewhere in the middle for nongendered bags.
| Best Use | Backpacking |
|---|---|
| Tested Lower Limit | 18 degrees (F) - EN |
| Tested Comfort | 30 degrees (F) - EN |
| Temperature Rating (F) | 18 degrees (F) |
| Temperature Rating (C) | -8 degrees (C) |
| Shell | Nylon |
| Zipper Location | Left |
| Insulation Type | Down |
| Water-Resistant Down | Yes |
| Fill | 650-fill duck down |
| Lining | Nylon |
| Sleeping Bag Shape | Semirectangular |
| Stuff Sack Size | 7.5 x 14 inches |
| Stuff Sack Volume | 10 liters |
| Gender | Men's |