The THERMOLITE® Reactor liner is our top selling and lightest thermal sleeping bag liner. With a mummy shape and Thermolite® Pro fabric, the Reactor Liner uses new infrared technology paired with comfortable stretch fabric to offer extra warmth, versatility, and increased insulation. The drawcord offers added flexibility for premium comfort. Best suited to cold conditions.


  • Thermal Boost of 12% when used in a 1 season sleeping and 6% in a 3 season bag
  • Stretchy, Thermolite® Pro fabric is incredibly comfortable and utilises Infrared Technology to increase warmth without adding weight.
  • Lighter weight and more packable than fleece.
  • Technical mummy-shape and available with or without a drawstring in the hood hood
  • Easy care – machine wash with no special soap is needed. Avoid fabric softeners and dryer sheets.
  • HEIQ Fresh bio based treatment for added odour control
  • Keeps sleeping bag clean.
  • Packs into its own Ultra-Sil stuff sack.
  • ADDED WARMTH - Up to 6% in a 3 season bag and +12 in a 1 season
  • BEST USE - Backpacking, Camping
  • COMES WITH - Ultra-Sil stuff sack
  • MATERIAL(S) - 50% Thermolite Pro & 50% Thermolite EcoMade
  • SHAPE - Mummy

We aim to ship out all orders placed before 2pm the same working day! For shipments in the United Kingdom mainland, we use Royal Mail Tracked 24 service (DPD Next Day for larger items and items that weigh over 4KG). Please see our shipping policy for more details.

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Sea To Summit Reactor Sleeping Bag Liner (Beluga Black)

RRP: £55.00 (Save £5.01) £49.99

Item is in stock Only 0 left in stock Item is out of stock Item is unavailable

Want it Friday, Jul 26, *UK Mainland Only, Order in next 16:08:38
SKU: ASL031061/2-BB
Barcode: 9327868158423


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