Get 10% Off & Free Priority Shipping By Joining The Live Ultralight Membership Here! Stay Warmer and Pack Lighter: Our micro polyester fabric weights only a few ounces, but can add another layer of insulation and warmth to your night&&';;s sleep! Keeps Your Sleeping Bag Cleaner: When the insulation in your sleeping bag is cleaner, it performs better keeping you warmer. By using our sleeping bag liners, you keep your sleeping bag clean of dirt, sweat and other debris. This means your bag stays cleaner and warmer for longer! Oh, and you can easily machine wash the liner whenever needed! Feels Like Home: Even though our technical Micro Polyester fabric is built be extremely tough and wick away moisture, it still feels like the sheets off your bed! Climb into the liner and feel like your back in the comfort of your own bed!