Sea to Summit Reactor Midweight Sleeping Bag Liner
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Product Description
MIDWEIGHT INSULATING SLEEPING BAG LINER WITH THERMOLITE® PRO TECHNOLOGY, STRETCH KNIT COMFORT, HEIQ FRESH ODOUR CONTROL AND SLEEP SYSTEM INTEGRATION
The Sea to Summit Reactor Midweight Sleeping Bag Liner is designed to boost your sleep system warmth with advanced Thermolite® Pro fabric. Built for backpacking, cycle touring, paddle touring and cooler nights outdoors, it adds meaningful warmth without unnecessary bulk.
Thermolite® Pro uses infrared-absorbing ceramic pigments and hollow-core fibres to trap and reflect body heat. When paired with a quality sleeping bag and mat, the Reactor Midweight can add up to 6°C of warmth to your sleep system.
The stretch-knit fabric and shaped arm openings allow unrestricted movement while you sleep, giving a more natural feel inside your bag. A technical shape and fitted hood help deliver extra warmth and comfort around the head and upper body without adding excess weight.
HeiQ Fresh odour control helps keep the liner fresher after extended use, while the quick-drying, machine-washable construction makes it easy to clean between trips. It also helps protect your sleeping bag from body oils and dirt, reducing wash frequency and helping extend your bag’s lifespan.
Available in Short, Regular and Long models, the Reactor Midweight Liner is a smart upgrade for cold sleepers, shoulder-season trips and anyone wanting a warmer, cleaner and more adaptable sleep setup.
BOOSTS SLEEP SYSTEM WARMTH
- Designed to enhance sleeping bag warmth without extra bulk
- Can add up to 6°C of warmth when paired with a quality sleeping bag and mat
- Ideal for backpacking, cycle touring, paddle touring and cooler-weather camping
- Useful for extending the comfort range of your existing sleep setup
THERMOLITE® PRO TECHNOLOGY
- Thermolite® Pro uses Far Infrared technology to help improve warmth
- Hollow-core fibres help trap and reflect body heat
- Infrared-absorbing ceramic pigments support thermal performance
- Designed for warmth, packability and low bulk
FREEDOM TO MOVE
- Stretch-knit fabric allows natural movement while sleeping
- Shaped arm openings help prevent restriction inside your sleeping bag
- Comfortable for sleepers who move or change position overnight
- Fits inside a range of sleeping bag shapes
TECHNICAL SHAPE AND HOOD
- Ergonomic design improves warmth and sleeping comfort
- Fitted hood helps retain warmth around the head
- Technical cut reduces excess fabric and unnecessary bulk
- Designed to work cleanly inside mummy-style sleeping bags
SLEEP SYSTEM INTEGRATION
- Snap connectors at the shoulders pair with Sea to Summit sleeping bags
- Quick-release front entry makes access easier
- Designed to stay aligned inside compatible Sea to Summit sleeping bags
- Works as part of a layered sleep system for changing conditions
EASY CARE AND LONGER BAG LIFE
- HeiQ Fresh odour control helps keep the liner fresher after extended use
- Quick-drying construction makes it practical for travel and multi-day trips
- Machine washable construction simplifies care
- Helps reduce wear and washing on your sleeping bag over time
- Helps preserve sleeping bag loft and extend sleeping bag lifespan
FABRIC COMPOSITION
- 100% post-consumer recycled polyester
- Stuff sack: 100% polyester
- Stretch-knit construction for comfort and movement
- Thermolite® Pro fabric technology
TECHNOLOGY
- Thermolite® Pro uses Far Infrared technology and hollow-core fibres
- Infrared-absorbing ceramic pigments help improve warmth
- HeiQ Fresh odour control helps keep the liner fresher for longer
- Snap connectors support Sea to Summit sleep system integration
SUSTAINABILITY DETAILS
- Crafted with certified recycled fibres
- bluesign® approved materials
- Helps reduce sleeping bag washing frequency
- Helps preserve sleeping bag loft and extend sleeping bag lifespan
CARE
- Machine washable
- Do not use fabric softener
- Air dry or machine dry on a cool to warm cycle without dryer sheets
- Dry fully before storing
- Store clean and dry between trips
| Specification | Details |
|---|---|
| Product Type | Midweight insulating sleeping bag liner |
| Available Models | Short, Regular and Long |
| Best Use | Backpacking, cycle touring and paddle touring |
| Material | 100% post-consumer recycled polyester |
| Stuff Sack Material | 100% polyester |
| Thermal Technology | Thermolite® Pro |
| Added Warmth | Up to 6°C when paired with a quality sleeping bag and mat |
| Odour Control | HeiQ Fresh |
| Construction | Stretch-knit fabric |
| Shape | Technical mummy-style shape with fitted hood |
| Arm Openings | Shaped openings for unrestricted movement |
| Sleep System Integration | Shoulder snap connectors pair with Sea to Summit sleeping bags |
| Entry | Quick-release front entry |
| Care | Machine washable and quick drying |
| Best Use Conditions | Cool nights, shoulder-season camping, lightweight travel and sleeping bag hygiene |
The Sea to Summit Reactor Midweight Sleeping Bag Liner is available in Short, Regular and Long models. Choose the model that best matches your height and sleeping bag length.
| Model | Weight | Dimensions | Packed Size | Recommended User Height |
|---|---|---|---|---|
| Short | 330 g | 178 x 80 cm | 19 x 11.5 x 11.5 cm | Up to 170 cm |
| Regular | 350 g | 193 x 80 cm | 19 x 11.5 x 11.5 cm | Up to 185 cm |
| Long | 365 g | 198 x 80 cm | 19 x 11.5 x 11.5 cm | Up to 198 cm |
How much warmth does the Reactor Midweight add to a sleeping bag?
The added warmth depends on your sleeping bag and mat setup, but the Reactor Midweight can add up to 6°C when paired with a quality sleeping bag and mat.
What is the Sea to Summit Reactor Midweight Sleeping Bag Liner best used for?
It is best used for backpacking, cycle touring, paddle touring, cool-weather camping, travel and improving sleeping bag hygiene.
What sizes are available?
This liner is available in Short, Regular and Long models.
What is the Reactor Midweight made from?
It is made from 100% post-consumer recycled polyester, with a 100% polyester stuff sack.
Which Reactor liner is the warmest?
The Reactor Fleeceweight is the warmest option, followed by the Reactor Midweight, then the Reactor Lightweight.
Can the Reactor Midweight work as a stand-alone sleeping bag?
In summer temperatures and still air conditions, it can function on its own for sleepers wearing long base layers. The fabric is not windproof.
Can the Reactor Midweight be machine washed and dried?
Yes. Reactor liners can be machine washed without special soaps. Do not use fabric softener. Air dry or machine dry on a cool to warm cycle without dryer sheets.
Which Reactor Midweight size should I choose?
Choose Short for users up to 170 cm, Regular for users up to 185 cm and Long for users up to 198 cm.
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