The Thermarest Synergy Sleeping Bag Liner adds warmth, comfort and years of life to any sleeping bag. Contributing up to 3 degrees of warmth to your sleeping system, the soft, stretch-knit polyester also serves as a protective barrier to your expensive sleeping bag's materials, absorbing the sweat and oils that would otherwise go directly into your bag and decrease its loft. Now, instead of washing and drying your entire bag or allowing that grime to clump up the insulation, all you have to do is remove the liner and toss it in the washing machine. A sleeping bag liner is also a must have for the ski tourer or alpinist as it is a requirement in most alpine huts, plus it takes away the itch factor when using the old WWII blankets in some French huts. Thermarest Synergy Sleeping Bag Liner Features Comfortable stretch knit fabric Wicking Adds warmth to your sleeping bag Drawcord hood closure Stuff sack Size:One Size: Fits 198cm Weight:340g Thermarest Synergy Sleeping Bag Liner