The THERMOLITE® Reactor™ liner is our top seller in the sleeping bag liner range. It's an excellent cold-weather option for those who need additional warmth. The hollow-core fibers trap heat and offer extraordinary insulating properties. This is a super stretchy, soft, and comfortable choice with a mummy shape, foot box, and a drawcord hood. Compact and lighter-weight than fleece, this is a best seller for good reason.
Packed Size Comparison
Similar to a small foam football
8.7 oz ≈ Two sticks of butter
Adds up to 14°F to the temperature range of your sleeping bag
Easy to wash and helps to keep your down bag cleaner for longer
- Adds up to 14°F / 8°C of warmth to a sleeping bag
- Lighter weight, more packable than fleece
- Mummy shape with a box foot
- Drawcord hood with mini cord lock
- Packs into its own Ultra-Sil™ stuff sack
The Reactor Series Sleeping bag liners, the Venture, Traverse and Basecamp synthetic Sleeping Bags and the foot boxes of the Women’s Altitude and Journey down Sleeping Bags use hollow core THERMOLITE® fiber to add warmth. These fibers trap extra air for insulation (just like the hollow-cores of polar bear or caribou fur).
In the liners, the knitted THERMOLITE® fabric is soft and stretchy and comes in three different weights: 80g/m² fabric used in the Reactor and the underside of the Compact Plus liners; a 110g/m² fabric which is used in the Extreme, and the core and foot box of the Compact Plus liner; and the Fleece, the warmest of all the fabrics.
THERMOLITE® is also used in the Air Sprung Cell sleeping mats.
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