A bag you can trust to get you through the single-digit temps. The Klymit 0 Full-Synthetic Sleeping Bag features pillowy synthetic fill that keeps you warm and comfortable all night long. Outer fabric has a durable water repellant treatment to protect the insulation from moisture that can impede thermal performance and add weight. But what you're really going to love about this sleeping bag is when the stretch baffles allow you to sit up, stretch, and freely cross your legs without unzipping your bag.