When temperatures dip, the heaviest collar zips in to cradle you in comfortable warmth,
As weather heats up, the lighter collar allows the perfect amount of ventilation and warmth and when things really heat up just remove the collar all together,
Gone are the days of needing 3 different sleeping bags for 3 different seasons! Comfort Rating: 23° F; Limit of Comfort -11° F, Extreme: -25° FCarry Weight: 37.1 oz./1052 g (sm), 41.4 oz./1174 g (md), 43 oz./1219 g (lg)Size: 37.4" x 66.9" (sm), 39" x 72.8" (md), 40.9" x 78.7" (lg)Carry Size: 7 LFill: Goose 850+Fill Weight: 20.1 oz./570 g (sm), 21.9 oz./621 g (md), 23.1 oz./655 g (lg)Shell: Asahi-Kasei 1.1oz Nylon 6.6 Rip-Stop - DWRLiner: Asahi-Kasei anti-static Polyester Rip-Stop - DWRFits To: 5'6" (sm), 6' (md), 6'6" (lg)No