MontBell's world patented Super Stretch™ System provides a night's sleep unlike any other. Durable elastic stitching in the baffles of the sleeping bag provide unmatched freedom of movement while simultaneously drawing the insulation closer to your body minimizing dead space to be heated throughout the night. Features: Super Stretch™ System Multi-Box Construction: engineered to maximize the warmth of the insulating material. Partitions have been created inside each baffle to more effectively distribute the down and limit migration. Tunnel Hood: a small face hole to improve warmth around your head and face Neck Adjuster: a drawstring adjusts fit around neck Neck Baffle: a shoulder collar prevents air circulation through top of the bag Draft Tube: a double draft tube prevents air from circulating through the zipper Foot Adjuster: a drawstring has been added to the last baffle, allowing the user increased adjustability. Auto Locking Zipper: a locking mechanism has been integrated to limit zipper "slip" during the night. Cotton sack included Specs: Temperature Rating: 0 F / -18 C Insulation: 650 fill power down 40-denier Multi-Filament Rip-Stop Full Dull Nylon Standard DWR treatment Max User Height: Reg (5ft 10in), Long (6 ft 4 in) Inside Shoulder Girth: Reg (53.2"–70.9"), Long (56.7"–75.6") Inside Knee Girth: Reg (42.8"–57.1"), Long (47.3"–63") Stuffed Size: Reg (7.9" x 15.6"), Long (8.5" x 16.8") Weight: Reg (3 lbs 6 oz), Long (3 lbs 12 oz) Fill Weight: Reg (1 lbs 14 oz), Long (2 lbs 1 oz) Size: R/ZIP/ L/ZIP Color: Sunrise Red