With Peregrine Endurance 0 degree sleeping bag we�ve prioritized continuous warmth insulating it with Perefill. A continuous fiber synthetic that is engineered to stay warm even in the most extreme conditions. With the Endurance your spring fever won�t have to wait until warmer night temperatures, featuring an articulated foot box specifically designed to keep your feet nice and toasty so you can sleep comfortably all night long. Other features include #10 YKK dual non-locking zippers that won�t have you fighting against fabric getting caught, water resistant polyester stuff sack to keep it dry during travel, and a hood and neck baffle for the extra layer of protection to keep the cold air out.