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💰 Value-Focused
🥾 Sea to Summit Reactor Insulated Sleeping Bag Liner — Review, Key Features & Current Price
A quick, search-friendly breakdown of performance, comfort, durability, and overall value—so it’s clear who this product fits and why.
🧭 How This Product Was Evaluated
- 👣 Comfort and usability for typical hikes
- 🧱 Materials and build quality for repeated outdoor use
- ⚖️ Value compared with similar products in the same category
- 🎒 Fit for beginner and casual hikers
📸 Product Images






🎯 Who This Is Best For
- 🧑🦯 Beginner hikers and casual outdoor users
- 🌲 Day hikes, light trails, and weekend trips
- 💵 Buyers prioritizing practical value
- 🗺️ General use in parks, trails, and travel hikes
💰 Current Price
Price & availability information
⚙️ Product Overview
🌟 Pros & Cons
- 🙂 Comfortable for most beginner hiking needs
- ⚖️ Balanced feature-to-price ratio
- 🧩 Easy to use with minimal setup
- 🧭 Versatile for different trail conditions
- 🏔️ Advanced users may want higher-end features
- 📏 Performance depends on correct size/fit
📝 Product Details
Product description
WE INVENT GEAR THAT ENABLES FREEDOM AND SELF-RELIANCE IN ANY ENVIRONMENT 
Camp Kitchen
Ultra-portable camp kitchen gear includes lightweight and collapsible cookware, dinnerware, utensils and more.

Sleep Systems
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.

Dry Storage
Space-saving stuff sacks and dry bags keep your camping gear dry and protected. Stay organized, easily access what you need, and keep on trekking.

Travel & Organization
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
4.7 out of 5 stars 218
4.4 out of 5 stars 89
4.4 out of 5 stars 363
3.9 out of 5 stars 27
4.0 out of 5 stars 33
4.7 out of 5 stars 19
5.0 out of 5 stars 5
Price
EUR 63.63EUR63.63
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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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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
🏁 Final Assessment
❓ Frequently Asked Questions
Is this suitable for beginners?
Yes. It’s designed to be easy to use and practical for people new to hiking.
What type of hiking is it best for?
Day hikes, light trails, and casual outdoor activities.
Is this good value for money?
It offers a balanced mix of features and price compared with similar products.
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Prices and availability are subject to change.
