Keep your sleeping bag clean, and sleep comfortably, in the Cocoon 100% Cotton MummyLiner. Fine yarn and a special weaving technique make the high quality cotton a very lightweight and durable fabric. It is breathable, very comfortable against your skin and creates a natural vapor balance. Cotton is durable, machine washable and colorfast. 100% premium quality cotton. Adds up to 5.3F. Light, durable, breathable, comfortable. Great for travel. Keeps sleeping bags clean. Machine washable and colorfast. Wt. 12 oz. Mummy Size: 95 x 3522 in.