Kelty Callisto 35 Degree Sleeping Bag Fill: Polyester Fiber; Shell: 100% Polyester; Liner: 100% Polyester Imported Temp Rating : 35 / 2C Insulation : CloudLoft Synthetic Weight 8 lb. 10 oz. Can be fully unzipped and opened flat for use as a blanket Differential cut to maximize loft and warmth