If youre adventuring in areas where you need a sleeping bag with this type of temperature rating, you better make sure its as dependable as its warm. The 40 degree Inferno has you covered with its water resistant Neovent Air fabric and 800 fill ProDownTM insulation, full draft collar and integrated draft overlap preventing heat loss, and trapezoidal side baffling. Water resistant Neovent Air fabric on hood, footbox, and back to protect moisture prone areas. 800 fill ProDownTM insulation. Generous cut allows user to wear more layers or to 'maytag in the bag. Full draft collar and integrated draft overlap for comfort and to prevent heat loss. Trapexoidal side baffle to prevent down migration. Center zip. Internal pocket for insulated storage. Compression sack and storage sack included. Good cinch cord seals out cold. Temp rating: 40AdegF 40AdegC. Weight: 3lb. 14 oz.. Stuff sack size: 12 x 22 in.. Imported.