Sea to Summit Comfort Blend Liner w Pillow SleeveA liner is the core of a sleep system, keeping your sleeping bag clean and improving your sleep climate. The Comfort Blend liner uses a stretch knit fabric made of polyester and TENCEL Lyocell fibers to create a soft, comfortable, moisture wicking layer around you. Features: The TENCEL Lyocell Polyester blend provides excellent moisture wicking and next to skin comfort HeiQ odour control technology helps keep the liner fresh even after extended use