Kelty Callisto 35 Degree Rectangular Synthetic Sleeping Bag, Autumn Fill: Polyester Fiber; Shell: 100% Polyester; Liner: 100% Polyester Imported Temp Rating : 35 / 2C Insulation : CloudLoft Synthetic Weight 4 lb. 6 oz. Can be fully unzipped and opened flat for use as a blanket Differential cut to maximize loft and warmth