Sea to Summit Reactor Thermolite Liner

The THERMOLITE Reactor liner is Sea to Summit's top seller in the sleeping bag liner range. It's an excellent cold weather option for those who need additional warmth. The hollow core fibers trap heat and offer extraordinary insulating properties. This is a super stretchy, soft, and comfortable choice with a mummy shape, foot box and a drawcord hood. Compact and lighter weight than fleece, this is a best seller for good reason.