Add warmth to your sleep system in cool or cold conditions: with our Reactor Liner. Using Thermolite® Pro fabric with infra red-absorbing ceramic pigments and Thermolite® EcoMade fibres , the new Reactor takes thermal performance to the next level. The stretch-knit fabric provides optimal comfort, and ensures the Reactor fits any sleeping bag. Choose between the classic Mummy and the Mummy with Drawcord - the footbox opening offers plenty of ventilation and the versatility of walking around camp while still wearing your liner if needed. Features Thermal boost to retain heat and warmth. As the core of your sleep system the Reactor liner extends the performance of your sleeping bag in colder conditions Thermolite® Pro technology using knitted, hollow-core fibres and infrared-absorbing ceramic pigments to reflect your body's heat back for enhanced warmth and comfort The classic Mummy version has practical openings in the shoulders to allow the user to stretch his or her arms out In the version with the drawcord footbox, the base or shuolder openings can be opened or closed for optimal comfort. They integrate perfectly with the Free-Flow Zip system in select Sea to Summit sleeping bags. Open the base drawcord, and you can hitch the liner up and walk round camp - perfect for bathroom breaks HeiQ Fresh odour control technology helps keep the liner fresh even after extended use Knitted fabric provides incredible stretch and freedom of movement - Reactor liners work perfectly with sleeping bags of any shape Sea to Summit Guarantee is offered for the Lifetime of this product