Sea to Summit Reactor Insulated Sleeping Bag Liner

Price: $74.95 - $69.99
(as of Jun 17, 2025 17:51:54 UTC – Details)

Product Description

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Sleeping pads, bags, liners, and pillows . . . when you’re weighing your options, the most important factor is the value of a great night’s sleep.

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Our collection of travel and outdoor accessories features a wide range of must-haves for organized, adventures.

Sea to Summit

Reactor Sleeping Bag Liner

Thermal boost liner retains heat, adds warmth to your sleep system in colder conditions, and acts as a hygienic layer to extend the life of your sleeping bag.

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Customer Reviews

4.6 out of 5 stars 123

4.2 out of 5 stars 59

4.4 out of 5 stars 347

4.7 out of 5 stars 26

4.4 out of 5 stars 21

4.7 out of 5 stars 11

5.0 out of 5 stars 2

Price

$69.99$69.99

$49.95$49.95

$164.25$164.25

$189.98$189.98

$169.00$169.00

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$579.00$579.00

Best for

Camping

Camping

Backpacking and Camping

Backpacking and Camping

Backpacking

2-Season Camping

2-Season Backpacking

Dimensions

85 x 31 inches

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72 x 25 x 4 inches

72″L x 21.5″W x 2.5″Th

72 x 22 x 2 inches

90.90 x 31.90 inches

83.1 x 32.5 inches

Weight

10 oz (284 g)

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1.4 pounds

1.4 pounds

1.33 pounds

4.72 pounds

1 lb 7.7 oz (672 g)

R-value or Temperature Grade

Adds up to 25F of warmth

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3.2

3.7

3.0

15°F (-9°C)

15°F (-9°C)

Non-PFAS

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✔

✔

✔

✔

✔

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About the Sea to Summit Reactor Sleeping Bag Liner

Sea to Summit Reactor series insulated sleeping bag liners can extend the comfort range and improve personal hygiene of any sleeping bag. Thermolite hollow core fibers are constructed like the fur of a polar bear, efficiently trapping heat and providing a luxuriously soft, comfortable feel. The stretch-knit fabric provides optimal comfort, and ensures the Reactor fits any sleeping bag. Additionally, the drawcord footbox offers plenty of ventilation and the versatility of walking around camp while still wearing your liner. Available in three different weights, Reactor technical liners make your existing sleeping bag warmer and more versatile. The Regular Liner uses hollow-core Thermolite Pro fabric with infra red-absorbing ceramic pigments and Thermolite EcoMade fibers. This lightweight fabric adds up to 14F of warmth to your sleep system. The Extreme Liner features a thicker hollow-core Thermolite Pro fabric to add up to 25F of warmth to your sleep system. The Fleece Liner employs hollow-core Thermolite Pro fibers in a grid-pattern to deliver our warmest sleeping bag liner which adds up to 32F of warmth to your sleep system.

thermolite
Imported
Insulated sleeping bag liner adds extra warmth and personal hygiene to any sleeping bag.
Thermolite Pro technology using knitted, hollow-core fibers and absorbing infrared ceramic pigments to reflect your body’s heat back to the wearer for enhanced warmth and comfort
Drawcord footbox can be opened or closed for optimal comfort and integrates perfectly with the footbox of our Free-Flow Zip system in select Sea to Summit sleeping bags
HeiQ Fresh odor control technology helps keep the liner fresh even after extended use
Knitted fabric provides incredible stretch and freedom of movement in this mummy-shaped liner and works seamlessly with sleeping bags of any shape, Sea to Summit Guarantee is offered for the Lifetime of this product