Sea To Summit Reactor Extreme Thermolite Liner

Sale price
List price
You save
$14.99 (20%)
This item is temporary out of stock

Using super-insulating 110g/m² THERMOLITE®, our Reactor Extreme is our warmest knit sleeping bag liner. The hollow core fibre threads work just like the hollow fur of a polar bear in that they trap heat effectively. When the mercury drops, you’ll appreciate the mummy shape and drawcord hood cinched down for extra warmth with its mini cord lock. The knit fabric also has serious stretch to it, making it an ideal liner for the restless sleeper.


  • Stretchy, Thermolite® fabric is incredibly comfortable
  • 110g/m² fabric is warmer than the 80g/m² Thermolite® used in the standard Reactor
  • Works like your favorite cold-weather base layer to trap insulating air and increase warmth
  • Easy care – no special soap is needed
  • Significantly improves the thermal performance of your sleeping bag
  • Comfortable stretchy fabric
  • Keeps sleeping bag clean
  • Machine wash and air dry - Avoid fabric softeners & dryer sheets to maintain wicking performance
  • Packs into its own Ultra-Sil™stuff sack

DIMENSIONS - 82 in / 208 cm
STUFF SACK SIZE - 6.5 x 4.5 in / 17 x 11.5 cm
WEIGHT - 14 oz / 399 g

You may also like


Easy Returns

Need to return an item? Check out our policy below
Return Policy

Lowest Price Guarantee

Find a better price? We'll beat it!
Price Match Policy