Sierra Designs DriDown Mobile Mummy 800-Fill 2 Season Sleeping Bag Ultralight jacket hood with no cords or toggles-it moves with you while fitting snug around your face like the hood on a jacket. Zipperless armports-no zippers or closers, ready for instant use Garment-style shoulder design-when youre upright in the bag, our tapered design rests on your shoulders-not your head. Centrally placed, ventable zipper on dual sliders can be zipped from bottom for venting. Sleeping bag comfort rating: 39 F, Limit 29 F,