Add extra warmth to your mummy sleeping bag for colder weather camping adventures with the Sea to Summit Reactor Extreme Mummy Sleeping Bag Liner. Made of advanced, 100% polyester Thermolite Pro hollow-core fiber fabric, this soft and warm stretch knit liner also features infrared-absorbing ceramic pigments to reflect your body's heat back to you for added warmth with great breathability. Lighter and more packable than a fleece liner, this sleeping bag liner adds greater warmth to a sleeping bag, plus it works well as a stand-alone bag in warmer weather. Designed for cold-weather mummy bags, this advanced liner also features a drawcord footbox that can be opened or closed for ventilation to ensure optimal comfort. This unique footbox design also allows you to walk around camp while wearing your liner if needed. Drawcord hood with mini cordlock for greater comfort. Weight: 12.8 oz. Mfrs. lifetime warranty. Imported.Manufacturer model #: A3208. 100% polyester Warm, comfortable, and advanced sleeping bag liner for mummy sleeping bags Features infrared-absorbing ceramic pigments to reflect your body's heat back to you Lighter and more packable than fleece liners Great stand-alone bag in warmer weather Drawcord footbox can be opened or closed for ventilation Drawcord hood with mini cordlock