Slumberjack Boundary -20 Sleeping Bag Polyester Taffeta External Velcro tabs combined with dual zippers create "arms out" functionality Right zipper extends around the footbox for increased ventilation and versatility Full length dual zipper design improves ventilation and comfort Layered, offset, quilt construction prevents cold spots Draft tubes along zippers keep out cold air and prevents heat loss Dual zip sliders for venting Offset layer construction with draft tubes Footbox shape allows natural comfortable position Cinching hood for cold weather comfort Includes stuff sack