Therm-A-Rest Synergy Sleeping Bag Liner

The soft and cozy Synergy Sleeping Bag Liner adds warmth, comfort, and years of life to any sleeping bag. Contributing up to 5°F/3°C 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.

Why let your sleeping bag take the brunt of a backpacking trip's grime and sweat? 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.