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  • Constructed of insulating Thermolite fabric, a hollow-core, breathable fiber that provides extraordinary warmth for its weight
  • Combined with the regular 80g/m² Thermolite, super insulating 110g/m² Thermolite panels provide added warmth in the torso and foot bed areas
  • Adds up to 20°F of warmth to a sleeping bag; can also be used as a summer ultralight sleeping bag
  • Liner helps keep the inside of your bag clean, saving it from the wear and tear of washings
  • Drawcord hood with mini cordlock cinches around face to hold warmth in
  • Mummy shaped liner features a 3D footbox providing plenty of room for feet
  • Sea to Summit Reactor Plus Themolite comes with a lightweight Ultra-Sil™ stuff sack
  • Compact, short design is ideal for women or anyone under 6 ft. tall


View all Sea to Summit Sleeping Bag Liners

REI membership


Best Use Backpacking
Sleeping Bag Shape Mummy
Added Warmth (F) Up to 20 degrees
Added Warmth (C) Up to 11.1 degrees
Stuff Sack Size 4 x 6 inches
Material(s) Polyester
Dimensions 72 x 36 inches
Weight 9.3 ounces
Weight - Metric 0.26 kilograms