A perfect sleeping bag is a versatile sleeping bag, and Western Mountaineering's got just that. The Everlite Sleeping Bag boasts a 45-degree rating, but it's as breathable and lightweight as a quilt. Western Mountaineering's design allows the bag to be used as a sleeping bag, as a blanket, or as insulation to wrap around yourself and your hammock. It can also be used as an overbag with another mummy to create an efficient cold weather system, and it offers open top and bottom sections with adjustable draw closures. There is no foot box for this sleeping bag due to its open design.