The comfy redwood rectangular sleeping bag is designed to be ultralight for warmer temps. Ideal for mild summer weather, short camping trips and sleepovers, the redwood weighs only 2 lb at 33 by 75 in. The insulation is synthetic hollow poly-therm that will not lose insulating efficiency when wet. It features a polyester shell and a polyester taffeta lining.2 lb of poly-therm hollow synthetic insulation, will not lose insulating efficiency if wetPolyester shell and polyester taffeta liner