Short || Reactor Fleeceweight Liner
Short
Reactor Fleeceweight Sleeping Bag Liner Reactor Fleeceweight Sleeping Bag Liner Reactor Fleeceweight Sleeping Bag Liner
New
Short || Reactor Fleeceweight Liner
Short
Reactor Fleeceweight Sleeping Bag Liner Reactor Fleeceweight Sleeping Bag Liner Reactor Fleeceweight Sleeping Bag Liner
New

Reactor Fleeceweight Sleeping Bag Liner

$84.95
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Highlights

Best Use: Cold-weather backpacking, Ski touring, (Stand-alone) summer use

Type: Thermal Liner

Weight: 12.9oz | 365g

Length: 70.1in | 178cm

Packed Size: 5.9 x 9.8 x 5.9 in | 25 x 15 x 15 cm

Performance
Weight
  • Ultralight
  • Lightweight
  • Midweight
Packability
  • Ultra Compact
  • Compact
  • Midsize
Climate
  • Warm
  • Cold
  • Extreme Cold
About The Product

Boost your sleep system’s warmth with the Reactor Fleeceweight. Thermolite® hollow-core fibers and grid fleece trap and reflect body heat, adding up to 8°C|14°F with minimal weight. The stretch fleece and arm openings allow freedom of movement, while snap attachments fit Sea to Summit sleeping bags for easy access. Easy to clean and quick-drying, it features HeiQ Fresh odor control. Using a liner reduces sleeping bag washes, helping preserve loft and extend lifespan.

Features

  • Boosts Sleep System Warmth – Reactor Fleeceweight uses Thermolite® hollow-core fibers and grid fleece to trap warmth with minimal added weight
  • 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
  • Stay Fresh Longer – HeiQ Fresh odor 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 fibers and bluesign APPROVED materials to minimize environmental impact
  • Can be used on its own as a lightweight sleeping bag in warm-weather conditions
Product Features

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Short || Reactor Fleeceweight Liner

Reactor Fleeceweight Sleeping Bag Liner Short

Short || Reactor Fleeceweight Liner

Reactor Fleeceweight Sleeping Bag Liner Short

Reactor Fleeceweight Liner

Boost your sleep system’s warmth with the Reactor Fleeceweight. Thermolite® hollow-core fibers and grid fleece trap and reflect body heat, adding up to 8°C|14°F with minimal weight. The stretch fleece and arm openings allow freedom of movement, while snap attachments fit Sea to Summit sleeping bags for easy access. Easy to clean and quick-drying, it features HeiQ Fresh odor control. Using a liner reduces sleeping bag washes, helping preserve loft and extend lifespan.

Features

  • Boosts Sleep System Warmth – Reactor Fleeceweight uses Thermolite® hollow-core fibers and grid fleece to trap warmth with minimal added weight
  • 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
  • Stay Fresh Longer – HeiQ Fresh odor 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 fibers and bluesign APPROVED materials to minimize environmental impact
  • Can be used on its own as a lightweight sleeping bag in warm-weather conditions

Technical Features

HEIQ Fresh
Thermolite Eco Made

Tech specs

  • Best Use
    Cold-weather backpacking, Ski touring, (Stand-alone) summer use
  • Material(s)
    100% Post-Consumer Recycled Polyester; Stuff Sack: 100% Polyester
Short
Regular
Long
Weight12.9oz 365g14.1oz 400g15.2oz 430g
Dimensions70.1 x 31.5 in 178 x 80 cm76.0 x 31.5 in 193 x 80 cm81.1 x 31.5 in 206 x 80 cm
Packed Size5.9 x 9.8 x 5.9 in 15 x 25 x 15 cm5.9 x 9.8 x 5.9 in 15 x 25 x 15 cm5.9 x 9.8 x 5.9 in 15 x 25 x 15 cm

Frequently Asked questions

How much warmth does a Reactor Fleeceweight add to a sleeping bag?

The added warmth depends on how well the sleeping bag retains heat and how well the sleeping mat insulates. When paired with a quality bag and mat, a Reactor Fleeceweight can add up to 8 °C / 14 °F.

Which Reactor is the warmest?

The Reactor Fleeceweight is the warmest option, followed by the Reactor Midweight, and then the Reactor Lightweight.

Can a Reactor Fleeceweight be used for backpacking or biking?

For bikepacking with frame bags or ultralight backpacking, the Reactor Fleeceweight is likely too bulky. Larger winter camping backpacks generally offer enough space.

Can a Reactor be machine washed and dried?

Reactor liners can be machine washed without special soaps. Do not use fabric softeners. Air dry or machine dry on a cool to warm cycle without dryer sheets.

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