The Thermolite Reactor Extreme liner is Sea to Summits 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. In warmer weather, it can be used a stand alone sleeping bag. The hollow core fibers of the THERMOLITE fabric work like hollow polar bear or caribou fur along with the knitted structure, this traps plenty of insulating air. Super-soft and amazingly stretchy, the Reactor Extreme uses a heavier version of THERMOLITE to provide extra warmth for an incredibly comfortable nights sleep. Use one to build your cooler-weather sleep system and to help to keep your sleeping bag clean, too.
The Thermolite Reactor Extreme liner is Sea to Summits 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. In warmer weather, it can be used a stand alone sleeping bag. The hollow core fibers of the THERMOLITE fabric work like hollow polar bear or caribou fur along with the knitted structure, this traps plenty of insulating air. Super-soft and amazingly stretchy, the Reactor Extreme uses a heavier version of THERMOLITE to provide extra warmth for an incredibly comfortable nights sleep. Use one to build your cooler-weather sleep system and to help to keep your sleeping bag clean, too.
in 2 offers
The lowest price for Sea to Summit Reactor Extreme Long Thermolite Liner right now is $84.99 at Davo's Tackle, compared across 2 retailers.
The all-time low was $68.00 on 28 Sept 2023 — today's price is 25% above the lowest ever. It has been notably cheaper before — worth setting a price alert.
Prices last updated 14 May 2026.
Sea to Summit Reactor Extreme Long Thermolite Liner
The Thermolite Reactor Extreme liner is Sea to Summits 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. In warmer weather, it can be used a stand alone sleeping bag. The hollow core fibers of the THERMOLITE fabric work like hollow polar bear or caribou fur along with the knitted structure, this traps plenty of insulating air. Super-soft and amazingly stretchy, the Reactor Extreme uses a heavier version of THERMOLITE to provide extra warmth for an incredibly comfortable nights sleep. Use one to build your cooler-weather sleep system and to help to keep your sleeping bag clean, too.
The Thermolite Reactor Extreme liner is Sea to Summits 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. In warmer weather, it can be used a stand alone sleeping bag. The hollow core fibers of the THERMOLITE fabric work like hollow polar bear or caribou fur along with the knitted structure, this traps plenty of insulating air. Super-soft and amazingly stretchy, the Reactor Extreme uses a heavier version of THERMOLITE to provide extra warmth for an incredibly comfortable nights sleep. Use one to build your cooler-weather sleep system and to help to keep your sleeping bag clean, too.
Last updated at 14/05/2026 17:08:44
Sea To Summit Thermolite Reactor Extreme Sleeping Bag Liner, Long
Delivery $11.99
Thermolite Reactor Extreme Liner
Free 60-day returns
| Length | 93 inches |
| Shape | Mummy |
| Is discontinued by manufacturer | No |
| Temperature rating | Extreme |
Sea To Summit Thermolite Reactor Extreme Sleeping Bag Liner, Long
Delivery $11.99
Thermolite Reactor Extreme Liner
Free 60-day returns
| Length | 93 inches |
| Shape | Mummy |
| Is discontinued by manufacturer | No |
| Temperature rating | Extreme |
