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Reactor Extreme Liner (Thermal Boost +15%)


Reactor Extreme Liner (Thermal Boost +15%)

Perfect for cold weather backpacking+ View tech specs
  • Size

BEST USE Backpacking & Camping

WEIGHT: 364 g


PACKED SIZE: 12 x 15 cm

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Reactor Extreme Liner (Thermal Boost +15%)
Reactor Extreme Liner (Thermal Boost +15%)


The THERMOLITE®Pro Reactor Extreme liner is Sea to Summit’s warmest knitted sleeping bag liner. If your adventures take you to colder climates, the Reactor Extreme will add plenty of warmth to a sleeping bag. Plus in warmer weather, it can be used as a ‘stand alone’ sleeping bag. With a mummy shape and Thermolite® Pro fabric, the Reactor Extreme Liner featuring a drawcord uses new infrared technology, which reflects the body's infrared heat back to you, paired with comfortable stretch fabric to add warmth, versatility, and increased insulation. The Reactor Extreme feature offers additional heat retention best suited to cold conditions.

Technical Features


Tech specs

  • Added Warmth
    Up to +15% 1 Season sleeping bag | 7% 3 Season sleeping bag
  • Best Use
    Backpacking, Camping & Winter Camping
  • Comes With
    Ultra-Sil stuff sack
  • Material(s)
    Thermolite Pro & Thermolite EcoMade
  • Shape
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