With a shape that gives you room to move and 650-fill-power down, the Sea to Summit Trek TkIII 10 sleeping bag is a warm choice for 3-season adventures, from backyard campouts to multiday treks.
Fill
650-fill-power Ultra-Dry premium down
Temperature Rating (F)
10 degrees (F)
- 650+ loft Ultra-Dry Down™; down is certified to the Responsible Down Standard (RDS)
- Full-length YKK #5 main side and foot zippers provide superior ventilation and allow the bag to be used as a comforter
- Shaped hood and oversize zipper draft tubes seal in warmth and keep cold out
- Internal pocket is ideal for a phone, GPS device or other valuables
- Includes a lightweight Ultra-Sil™ compression bag and storage cell
- Forms a snug double sleeping bag by zipping to any Altitude, Journey or Venture sleeping bag (not included)
- Sea to Summit guarantee is offered for the lifetime of this product; see manufacturer's website for details
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 | 10 degrees (F) - ISO |
| Tested Comfort | 21 degrees (F) - ISO |
| Temperature Rating (F) | 10 degrees (F) |
| Temperature Rating (C) | -12 degrees (C) |
| Shell | 30-denier nylon |
| Zipper Location | Left |
| Insulation Type | Down |
| Water-Resistant Down | Yes |
| Fill | 650-fill-power Ultra-Dry premium down |
| Lining | 30-denier nylon |
| Sleeping Bag Shape | Semirectangular |
| Stuff Sack Size | 8 x 18 inches |
| Stuff Sack Volume | 14 liters |
| Gender | Unisex |
| Sustainability | Down certified to the Responsible Down Standard (RDS) |