Sea to Summit Thermolite Reactor Extreme Sleeping Bag Liner

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This Sea to Summit Thermolite Reactor Extreme sleeping bag liner adds a full 25°F of warmth and extends the life of your sleeping bag.

  • Features

    • Constructed of insulating Thermolite® fabric, a hollow-core, breathable fiber that provides extraordinary warmth for its weight
    • Adds up to 25°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
    • Comes with a lightweight Ultra-Sil™ stuff sack
    View all Sea to Summit Sleeping Bag Liners
  • Technical Specs

    Best Use


    Sleeping Bag Shape


    Added Warmth (F)

    Up to 25 degrees

    Added Warmth (C)

    Up to 14 degrees

    Stuff Sack Size

    3 x 5 inches




    84 x 36 inches


    14 ounces

  • Reviews
    322 reviews with an average rating of 4.4 out of 5 stars

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