Yawn Patrol 15 Sleeping Bag

Roomy and down-insulated, this 15° Mountain Hardwear sleeping bag keeps you comfortable on summer nights. The curved rectangular shape lets you sleep easy. And you can also wear it like a parka.

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.