The Reactor Fleeceweight Liner by Sea to Summit is the stretch-it-on, fleece-it-up solution for boosting warmth in every cold-weather sleep system!

Built with Thermolite® hollow-core fibres and grid fleece, this liner traps warmth with minimal added weight for serious insulation on chilly nights. Stretch-knit fabric and shaped arm openings allow unrestricted movement for natural comfort throughout your sleep, while the ergonomic design with a fitted hood delivers optimal warmth without extra weight or bulk. Snap connectors at the shoulders easily pair with Sea to Summit sleeping bags for quick, hassle-free entry and exit, and HeiQ Fresh odour control technology keeps the liner fresh after extended use. Machine washable construction simplifies care while reducing wear on your sleeping bag over time, and it's crafted with certified recycled fibres and bluesign APPROVED materials for lower environmental impact. Versatile enough to use on its own as a lightweight sleeping bag in warm-weather conditions too.

The Sea to Summit Reactor Fleeceweight Liner is the stretchy, fleece-backed warmth boost for every alfresco sleep!

• Thermolite® hollow-core fibres and grid fleece trap warmth with minimal added weight
• Stretch-knit fabric and shaped arm openings allow unrestricted movement for natural comfort
• Ergonomic design with fitted hood delivers optimal warmth without extra weight or bulk
• Snap connectors at shoulders pair with Sea to Summit sleeping bags for easy entry and exit
• HeiQ Fresh odour control technology keeps liner fresh after extended use
• Machine washable — simplifies care and reduces wear on sleeping bag
• Can be used on its own as lightweight sleeping bag in warm weather