Halti Skrollan +40 Degree Superlite Mummy Sleeping Bag polyester Shell: Ripstop polyester with water repellant treatment Lining: Soft touch polyester, a material that transfers moisture away from the skin Fill: Quattrofil 7, 7 hole hollow fibre. One-layer structure is lightweight Zipper is protected by a thermal flap, preventing heat loss through the zipper