Get Schooled in the Geometry of ComfortRemember the trapezoid from 10th-grade geometry? Turns out, this funky ol shape is ideal for helping sleeping bag baffles retain heat. The trapezoidal baffle construction improves on our best-selling Cosmic sleeping bag-and it's just one of the reasons the Kelty Cosmic Down 0 is still our favorite three-season superstar. We also love the natural-fit foot box for happier feet, and a PFC-free water-repellent coating for a healthier environment.FeaturesInnovative trapezoidal baffle construction = thermal efficiencyLightweight and warm 550 fill downEnvironmental and health friendly C0 and PFC-free DWR fabricsZippered internal stash pocket for headlamp, cell phone or actual stashButtery-soft and durable 20D Nylon shell fabricZipper draft tube with anti-snag zipper design makes it easy to get in and outDual slider for ventilation with locking zippersNatural fit spacious footbox = more room to wiggle your toesComes with stuff sack for quick departuresSpecificationsRegularISO Comfort Rating: 17°F / -8°CISO Limit Rating: 4°F / -16°CISO Extreme Rating: -34°F / -37°CFits to: 6' 0" / 183 cmWeight: 4 lb. 9 oz. / 2.07 kgFill weight: 39.51 oz. / 1120 gStuffed size: 10" x 19" / 25 x 48 cmMaterialsInsulation: 550FP Duck DownShell material: 20D 400T NylonLiner material: 50D 300T PolyesterSource: Imported Kelty Cosmic 0 Deg 550 Down Sleeping Bag, Regular Size, Right-Hand