Sea to Summit Reactor Thermolite Fleece Sleeping Bag Liner
Built with Thermolite® fabric and grid fleece, the Sea to Summit Reactor Thermolite Fleece sleeping bag liner boosts the performance of your cold-weather sleep system by improving warmth retention.
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- As the core of your sleep system, the Reactor liner extends the performance of your sleeping bag and sleeping mat in the coldest of conditions
- Hollow-core Thermolite EcoMade fibers are used in a grid-pattern fleece for maximum warmth retention
- Drawcord footbox can be opened or closed for optimal comfort and integrates perfectly with the footbox of the Free-Flow Zip system in selected Sea to Summit sleeping bags
- HeiQ Fresh odor control technology helps keep the liner fresh even after extended use
- Mummy shape is designed for maximum thermal efficiency and includes shoulder zippers and footbox drawcord for additional temperature regulation
- Sea to Summit Guarantee is offered for the lifetime of this product
Imported.
View all Sea to Summit Sleeping Bag Liners| Best Use | Backpacking |
|---|---|
| Sleeping Bag Shape | Mummy |
| Added Warmth (F) | Unavailable |
| Added Warmth (C) | Unavailable |
| Stuff Sack Size | Unavailable |
| Material(s) | 60% Thermolite All-Season EcoMade recycled polyester/40% recycled polyester yarn |
| Dimensions | Standard: 85 x 31 inches Compact: 78 x 31 inches |
| Weight | Standard: 14.8 ounces Compact: 13.8 ounces |
| Sustainability | Contains recycled materials |
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The extra layer of warmth I needed!
Cold sleeper here! I own a Western Mountaineering Uberlite 30 degree bag, which is super light but definitely not enough to keep me warm under 45 degrees. This fleece liner does the trick! I even made it through a night at 22 degrees (although with extra layers!!). The only drawback is the liner gets static when I wear my Wool layers, and since the zipper doesn't go all the way down you might find yourself somewhat "tangled" due to the fabric getting static-ey. Most importantly, it keeps me warm on those cold nights where I would otherwise have to invest in another, warmer and heavier sleeping bag. Good investment for me, 100%.
Best investment
[This review was collected as part of a promotion.] The Sea to Summit Reactor Fleece Sleeping Bag Liner is a fantastic product and a much needed one for camping. It provides extra warmth on chilly nights, extending the usability of sleeping bag into colder seasons. The fleece material is so soft and cozy. it’s lightweight and packs down making it easy to transport. I used it when I went camping last weekend and i will say , this will be a best investment for those who go camping. Love mine.
Reactor fleece sleeping bag liner
[This review was collected as part of a promotion.] The reactor fleece sleeping bag liner is very soft even though it’s not what I was expecting I figured it would be like a silky material but it was more like cotton but other than that it could fit like 2 people in it! And it definitely still keeps you warm! I would still recommend!
Great Liner, Better Summer Sleeping Bag
I bought this a couple years ago since I tend to be a cold sleeper and wanted to upgrade my 30 degree bag for winter camping. It helps add about 10 degrees of warmth and I slept fine on a 20 degree night. What I like more about this liner is using it in the summer. This liner is great down to about 50 degrees with a base layer on and it's really nice since this is about the the size of half a loaf of bread. On the negative side, I am 6 foot tall and just barely fit in this and it is still a little uncomfortable so I usually sleep with my head out of the liner and wear a hat. It's also a really tight liner, so I found the need to stuff some clothes into my sleeping bag to fill a couple voids of dead air.
We Survived -10°F in New Hampshire: Sea to Summit Fleece Liner Kept Us Warm!
[This review was collected as part of a promotion.] Our Boy Scouts of America troop braved the annual Klondike adventure in New Hampshire, facing temperatures as low as -10°F. Proper layering and quality gear were essential, and the Sea to Summit fleece liner proved to be a game-changer. Combined with a 15°F sleeping bag and a thermal liner, the fleece liner added a noticeable boost in warmth and comfort. It effectively trapped heat, prevented cold spots, and made a significant difference in overall insulation. The soft fleece material was cozy, and despite the extreme conditions, we woke up warm and well-rested. Highly recommend this for anyone looking to enhance their sleeping system in cold-weather camping.
Definitely improves the warmth of your bag.
This fleece liner is great for improving the warmth rating of sleeping bags and is definitely worth the extra space in your bag. I used the Sea to Summit Thermolite Reactor Fleece Liner to increase the warmth of my sleeping bag. I found it to be very soft and comfortable and enjoyed using it to sleep while on the trail. In addition, the packed size is small and at only 14.8oz it is worth carrying if there is any worry your sleeping bag may not be enough. I have seen some reviews say that it can be used as a summer sleeping bag. While that is not my intended use, I can absolutely picture someone doing that if they are interested in ultralight summer backpacking.
Really Works
I slept in my 15 degree sleeping bag with this liner and woke up to a -10 F morning. It was a comfortable night. I did have a good groundpad and I wore some of my layers
The best of the reactor series
I have tried using the Reactor Plus in the past and did not feel any additional warmth. I then started to doubt the validity of thermolites efficiency and have since relied on the use of the SOL escape bivvy for additional warmth. Early 2016 I saw the new Thermolite Reactor Fleece and have used the reactor fleece on few outings both in wintery conditions at 28 F in march to add warmth to my 40 F Quilt and during this summer by itself down into the 60's. The Reactor Fleece certainly works. The material feels great next to skin and unlike the SOL Escape bivvy it won't make crinkly noises as you toss and turn. My issue with the product is that it is pricey and at 13 oz is a good 5 oz heavier and not as compact as the SOL Escape Bivvy. (Ultralight Guys will understand) The SOL Bivvy is also warmer. The two products when used in together is as warm as your standard summer down bag like those 45 F sleeping bags. It's a great product, but again it is on the pricey side.
Great liner!
[This review was collected as part of a promotion.] Great compactable mummy liner! This is an waffle like texture and super warm for for insulating your sleeping bag. Very versatile for all sizes and have great cords to adjust size around head and feet. Perfect for backpacking and camping.
Highly satisfied
[This review was collected as part of a promotion.] Really satisfied with the feel of the material, the durability, and effectiveness of the bag liner. I got the extreme version because I wanted to be able to pair it with my 20° bag and get more range and extend its life. I also planned to use the bag liner as a hot summer night sleeping bag. It’s also much easier to wash than a sleeping bag. So it’s nice to use on the trip. Turns out my favorite use for it is as a summer bag. It’s very small when packed compared to a sleeping bag and works well to keep you comfortable on a backpacking or bike-packing trip on warm nights