The Marmot Cwm is a familiar model, as it's been made for years. For this season, like many other Marmot sleeping bags, the Cwm has been redesigned and the traditional zipper has been replaced with three special ones: you can stick both hands out of the bag if you want, without opening the main zipper. The fabric is equipped with a wind and waterproof membrane - it protects the down from getting wet, when sleeping in a snow cave or cramped tent. With this caliber of winter sleeping bags, the otherwise excellent EN sleeping bag standard is quite useless - the test does not bring out the differences between heavyweight winter bags properly. According to the manufacturer, -40ºC is the lowest temperature at which the bag can be used for sleeping, not just for surviving. - Regular size: suits max. 183 cm users, shoulder girth 160 cm, hip girth 144 cm, foot box girth 112 cm - Insulation down: fillpower 800, amount 1419 grams, RDS certified - The down is Down Defender treated to repel