Features: Ultralight sleeping bag liner with integrated CELLIANT(R) bioceramic recovery technology Designed to support more complete overnight recovery and help reduce fatigue CELLIANT(R) technology helps maintain an optimal sleeping temperature whether you run hot or cold Clinically demonstrated to increase local circulation, improve cellular oxygenation, promote restful sleep, enhance performance, and speed recovery Soft woven fabric adds comfort to your sleep setup in both backcountry and frontcountry environments Functions as a standalone packable layer for travel or warm-weather nights under the stars Durable, outside-facing seam construction feels smooth and comfortable against the skin Helps keep dirt, odor, and body oils out of your sleeping bag with an easy-to-wash removable liner Reversible design fits both right-zip and left-zip sleeping bags Minimalist cinch-hood closure allows one-handed temperature regulation Storage: Includes a stuff sack for compact packing and easy transport