The Cocoon sleeping bag is thermally efficient by design and is insulated with the new Primaloft SB insulation (20% more loft than Primaloft Sport). The 30” centre zipper closes to the neck and snugs the bag around the shoulders, eliminating the need for a draft collar. The close fitting hood works like a jacket hood and uses considerably less fabric and insulation than used in the classic sleeping bag design. Shock cord and linking toggle closure allow the hood to be drawn in closely to form a tunnel above mouth and nose for chilly nights. A great choice for the lightweight crowd.