Manufacturer:

Sea to Summit Reactor Midweight Liner

The Sea to Summit Reactor Midweight Liner is a versatile thermal sleeping bag liner designed to add warmth, comfort, and hygiene to your sleep system. Made with stretch-knit Thermolite® Pro fabric and Far Infrared (FIR) technology, it helps trap and reflect body heat, adding up to 6°C of extra warmth without excess bulk. Integrated armholes and stretch construction allow unrestricted movement throughout the night, while HeiQ Fresh odour control keeps the liner fresher on extended trips. Lightweight and quick-drying, it’s ideal for backpacking, camping, bikepacking, and travel.

The Sea to Summit Reactor Midweight Liner is a high-performance thermal liner built to boost warmth and comfort across a wide range of adventures. Constructed from stretch-knit Thermolite® Pro fabric with hollow-core fibres and Far Infrared (FIR) technology, it efficiently traps and reflects body heat to add up to 6°C of extra warmth when used as part of a sleep system. Designed for unrestricted comfort, the liner features integrated armholes and flexible stretch construction, making it ideal for side sleepers and restless sleepers alike. It fits inside any sleeping bag and can snap directly into compatible Sea to Summit sleeping bags for easier entry and exit. HeiQ Fresh odour-control treatment helps maintain freshness during multi-day trips, while the quick-drying fabric makes the liner easy to clean and maintain. By reducing the need to frequently wash your sleeping bag, it also helps preserve insulation loft and extend the life of your sleep system. Lightweight and compact, it’s well suited to backpacking, winter camping, hut trips, bikepacking, and travel.

Features:
Stretch-knit construction for unrestricted movement
Integrated armholes for comfort in any sleeping position
Thermolite® Pro fabric with FIR heat-reflective technology
Hollow-core fibres improve warmth retention
Adds up to 6°C / 11°F of warmth to a sleep system
Quick-drying and easy to clean
HeiQ Fresh odour-control treatment
Compatible with all sleeping bags
Snaps into compatible Sea to Summit sleeping bags
Helps extend sleeping bag lifespan by reducing wash frequency
Includes Ultra-Sil stuff sack

Specifications:
Added warmth: Up to 6°C
Best use: Backpacking, camping, winter camping
Shape: Mummy
Materials: Thermolite Pro & Thermolite EcoMade
Included: Ultra-Sil stuff sack
Best Use: Backpacking & Camping
Weight: 350g (Regular)
Max User Height: 185cm (Regular)

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The Sea to Summit Reactor Midweight Liner is a high-performance thermal liner built to boost warmth and comfort across a wide range of adventures. Constructed from stretch-knit Thermolite® Pro fabric with hollow-core fibres and Far Infrared (FIR) technology, it efficiently traps and reflects body heat to add up to 6°C of extra warmth when used as part of a sleep system. Designed for unrestricted comfort, the liner features integrated armholes and flexible stretch construction, making it ideal for side sleepers and restless sleepers alike. It fits inside any sleeping bag and can snap directly into compatible Sea to Summit sleeping bags for easier entry and exit. HeiQ Fresh odour-control treatment helps maintain freshness during multi-day trips, while the quick-drying fabric makes the liner easy to clean and maintain. By reducing the need to frequently wash your sleeping bag, it also helps preserve insulation loft and extend the life of your sleep system. Lightweight and compact, it’s well suited to backpacking, winter camping, hut trips, bikepacking, and travel.

Features:
Stretch-knit construction for unrestricted movement
Integrated armholes for comfort in any sleeping position
Thermolite® Pro fabric with FIR heat-reflective technology
Hollow-core fibres improve warmth retention
Adds up to 6°C / 11°F of warmth to a sleep system
Quick-drying and easy to clean
HeiQ Fresh odour-control treatment
Compatible with all sleeping bags
Snaps into compatible Sea to Summit sleeping bags
Helps extend sleeping bag lifespan by reducing wash frequency
Includes Ultra-Sil stuff sack

Specifications:
Added warmth: Up to 6°C
Best use: Backpacking, camping, winter camping
Shape: Mummy
Materials: Thermolite Pro & Thermolite EcoMade
Included: Ultra-Sil stuff sack
Best Use: Backpacking & Camping
Weight: 350g (Regular)
Max User Height: 185cm (Regular)

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