The Sea To Summit Reactor Lightweight Liner increases your sleeping bag’s warmth with minimal added weight. Designed for versatility and comfort, it features stretch-knit Thermolite® Pro fabric that moves with you as you sleep, while integrated armholes provide complete freedom of movement for unrestricted rest.
The liner fits easily inside any sleeping bag and snaps into compatible Sea to Summit bags for secure placement and effortless entry and exit.
Using Far Infrared (FIR) technology and hollow-core fibres, Thermolite® Pro traps and reflects body heat, boosting warmth by up to 4 °C | 7 °F without adding bulk or weight.
With HeiQ Fresh odour control and quick-drying performance, the Reactor Lightweight Liner stays fresh and easy to maintain on extended trips. It also helps extend the lifespan of your sleeping bag by reducing the need for frequent washing, keeping insulation loft and performance intact for longer.

Sea To Summit Reactor Lightweight Liner Features:

• Freedom to Move: Stretch-knit construction and armholes provide unrestricted comfort for any sleep position.
• Lightweight Thermal Boost: Thermolite® Pro with FIR and hollow-core fibres adds up to 4 °C | 7 °F warmth.
• Easy to Clean: Quick-drying and machine washable with HeiQ Fresh odour control treatment.
• Compatible Design: Fits all sleeping bags and snaps into Sea to Summit bags for secure positioning.
• Protects Your Sleeping Bag: Reduces washing frequency to maintain insulation loft and extend bag lifespan.
• Ideal for backpacking, travel, hut stays, and warmer-weather adventures.

Sea To Summit Reactor Lightweight Liner Specifications:

• Added Warmth - Up to 4°C
• Best Use - Backpacking, Camping & Winter Camping
• Comes With - Ultra-Sil stuff sack
• Material(s) - Thermolite Pro & Thermolite EcoMade
• Shape - Mummy
• Fits Up to Height - 185cm
• Weight - 255g