Sea to Summit Trek 30F Sleeping Bag

The flexibility of the Free-Flow Zip System—which lets you use it a quilt or wear it—plus its roomy shape make the Sea to Summit Trek 30F sleeping bag a comfy choice in cool-to-warm conditions.

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.

• RDS-certified, 650+ fill-power duck down with a non-PFAS Ultra-Dry Down treatment to stay drier in damp conditions
• Recycled 20-denier polyester shell with a non-PFAS durable water repellent (DWR) finish blocks wind and moisture
• Polyester liner provides pure comfort
• Free-Flow Zip System allows you to open the bag sequentially for ventilation up to the point where it is opened flat as a quilt
• With the Free-Flow Zip System, you can even secure the snaps around your shoulders, open the footbox zipper and 'wear' the Trek around camp
• Tapered-rectangular fit is designed for spacious comfort when you're camping or traveling
• Sea to Summit Guarantee is offered for the lifetime of this sleeping bag