A TravelSheet is an extremely lightweight and roomy sleep sack or sleeping bag liner. These versatile sheets are excellent as a warm weather sleeping bag or a rectangular sleeping bag liner. Compact and lightweight, TravelSheets are ideal to bring to hotels, youth hostels, alpine huts, boats, planes, trains, or anywhere else you might travel. 100% Polyester CoolMax is the fastest drying moisture management fabric. Its four-channel fibers move sweat away from your body. CoolMax is highly breathable and easy to care for. CoolMax TravelSheets wick moisture away from your body and keep you dry and comfortable. They do not have a side opening or a zipper for best performance.