Optimised for minimal weight and maximum warmth, the Reactor Lightweight enhances sleep system performance with advanced Thermolite® Pro fabric, which uses infrared-absorbing ceramic pigments and hollow-core fibres to trap body heat. Adding up to 4°C|7°F of warmth with minimal bulk, it’s ideal for ultralight expeditions. Stretch-knit fabric and articulated arm openings ensure unrestricted mobility. Treated with HeiQ Fresh odour control, it’s quick-drying, machine washable, and helps prolong your sleeping bag’s lifespan by reducing wash frequency.
- Lightweight and insulative, Thermolite® Pro technology with hollow-core fibres and infrared-absorbing pigments enhances warmth with minimal pack size
- Freedom to Move – Stretch-knit and shaped arm openings allow unrestricted movement, providing natural comfort throughout your sleep
- Technical Shape and Hood – Ergonomic design with a fitted hood delivers optimal warmth and comfort without extra weight or bulk
- Fits any sleeping bag – Stretch fabirc means the Reactor Liner fits any shape of sleeping bag
- Stay Fresh Longer – HeiQ Fresh odour control technology keeps the liner fresh after extended use
- Sleep System Integration – Snap connectors at the shoulders easily pair with Sea to Summit sleeping bags for quick, hassle-free entry and exit
- Easy to Keep Clean – Machine washable construction simplifies care and reduces wear on your sleeping bag over time
- Lower Impact Materials – Crafted with certified recycled fibres and bluesign APPROVED materials to minimise environmental impact
TECH SPECS
Weight
S: 235g
R: 255g
L: 260g
Certification
RCS – 1114661
Dimensions
Short: 80 x 178cm
Regular: 80 x 193cm
Long: 80 x 198cm
Ideal for
Backpacking, Cycle touring, Paddle touring
Packed dimensions
10 x 10 x 18cm
Recommended user height
S: 170cm
R: 183cm
L 198cm
