US Military 4-PC Weather Resistant Modular Sleep System with Waterproof Gore-Tex Cover The system consists of two Mummy-style sleeping bags (Warm & Cold weather), a Water-proof Bivy, and a Compression Sack - 4 Piece System Will go down to extreme temperature of -30 Used in environments ranging from mild to extremely cold weather Flame retardant, and machine washable. Genuine U.S. Army Modular Sleeping System NEW in Sealed Package