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Sea To SummitThermolite Reactor Extreme Sleeping Bag Liner

Sea To SummitThermolite Reactor Extreme Sleeping Bag Liner

Select a color:Orange

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4.5 out of 5 stars
33 Reviews

Staying warm means staying happy.

The Sea to Summit Thermolite Reactor Extreme Sleeping Bag Liner is a great way to get an extra season out of your sleeping bag or stay warm in unpredictable weather. Lightweight and highly breathable Thermolite fabric will add up to 25 degrees Fahrenheit to your bag’s temperature rating at a low cost of 399 grams added to your pack. The Reactor Extreme has a mummy shape to mesh with your sleeping bag and a draw cord hood that can be cinched up when it’s really cold.


  • Sleeping bag liner adds up to 25 degrees to sleeping bags
  • Thermolite insulation is light, breathable, and packable
  • Included stuff sack
  • Item #STS0084

Tech Specs

Degrees Added
Claimed Weight
Recommended Use

Overall Rating

4.5 based on 33 ratings

Review Summary

5 Stars - 22 reviews
4 Stars - 8 reviews
3 Stars - 2 reviews
2 Stars - 1 reviews
1 Stars - 0 reviews

Fits Small

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Runs smallTrue to sizeRuns large

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