Sea to Summit Reactor Thermolite Extreme Sleeping Bag Liner
Powered by Thermolite® Pro fabric that uses an innovative infrared technology, the Sea to Summit Reactor Thermolite Extreme sleeping bag liner provides exceptional warmth in colder weather.
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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
- Thermolite Pro technology uses knitted, hollow-core fibers and absorbing infrared ceramic pigments to reflect your body's heat back for enhanced warmth and comfort
- 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
- 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
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) | 50% Thermolite Pro yarn/50% Thermolite EcoMade recycled polyester yarn |
| Dimensions | Standard: 85 x 31 inches Compact: 78 x 31 inches |
| Weight | Standard: 12.8 ounces Compact: 12.1 ounces |
| Sustainability | Contains recycled materials |
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Bacon saver
I was up on black mountain when a crazy cold front came through..0 degrees, -19 with the wind chill...and this with my 15 degree marmot bag kept me warm all night. Seriously I pulled this out of the bag and was skeptical that it would add that much warmth but it saved me. I had picked a bad spot to post up for the night and with high winds I woke up to a nice layer of snow and ice in my tent but I was warm and this thing was the reason why. Look forward to using it as a summer bag as well! Also..please allow and 10 degree variance when shopping for these things just to be on the safe side..just a tip from a fellow piece of hiker trash
Fantastic!
I use this liner in a 0 degree Mountain Hardwear bag. It protects the bag and keeps it clean. The best part is the warmth. It is very comfortable and feels similar to silk. The draw cord sinches around your shoulders and keeps your body heat in. I prefer winter camping and love the snow. This liner is a great addition to any mummy bag if you are going to be in cold climates. If it gets wet, it dries quickly. Once it is stuffed into the sack that comes with the liner, I throw that into my sleeping bag and pack them together for convenience. It is very simple to wash once your make it home. I've recommended this to several friends!
Good Stuff
I tend to buy a lot of gear- my wife says we have a mini REI in our basement. That being said, I sometimes buy gear that I use once, don't really like it and rarely use it again. I feared this liner would fall into this category, but I was wrong. It works great to add extra warmth to a sleeping bag, stands alone for a summer bag in warm places, and acts as a great liner when staying at a friend's cabing or home and don't want to have to wash all the sheets after the visit. It is a very soft, stretchy material that makes it feel larger than it is, making it very comfortable. It was pricey, but I am very pleased with the purchase.
Perfect. Lightweight, inexpensive, warm.
Used during a 3-day AT hike through Maryland in early December. Perfect way to add another layer of warmth without purchasing an entirely new sleeping bag rated for colder weather. Added a surprising amount of warm given that it's so thin. The liner is considerably less expensive than another sleeping bag, is incredibly lightweight, and very comfortable. I did not feel any "bunching" or "wrapping" while in my sleeping bag (the liner moved and rotated with my body. Completely worthwhile investment. If you're a cold-natured person, consider the same liner that "adds more warmth"; hot-natured people, consider the lighter version.
Great for travel
I bought this liner because I was worried about being cold on my trek to Annapurna Base Camp. I didn't realize how WARM it was there during monsoon season! Regardless, I ended up using the liner by itself on top of beds, under not-so-clean-looking blankets at various teahouses along the route, and a few times as an actual liner inside my sleeping bag. It was one of my favorite things I took along to Nepal. I love that it is lightweight and also stretchy, so if you use it without a sleeping bag, you don't really feel like you are in a confined space like you would in a mummy bag. Also, it is compact and lightweight--a great purchase!
great add on for cold weather and summer
I have used this bad as a liner and by itself on many occasions. In extreme cold it will lock in heat and compliment the best down bags when you have cold near zero temps. It will improve your bags rating about 10 to 20 degrees. This bag is not confining either. There is plenty of room for moving around in it as well. In warm summer months its just right to use by itself with temps above 60f or as a sleep sheet with a thin bag. It packs down to about the size of a soda can and takes up little space. I think its a good product and has kept me nice an warm when waking to ice condensation on the inside of the tent cold.
Makes all the difference
I'm a cold sleeper, and though I have a WSD 0 degree sleeping bag, I still got quite chilly on nights that dipped much below 30 degrees partially due to how roomy the bag is (and that was wearing 2 thermal layers on the bottom, wool socks, 2 thermals on top, a down jacket, and a hat). Adding the Thermolite Reactor Extreme made a huge difference in my comfort level. While it doesn't add 25 degrees to the bag, it does keep chilly drafts away and ensured that I slept soundly; it's warmth to weight ratio is very good. Additionally, it keeps one's sleeping bag a bit cleaner on extended backcountry voyages. Definitely recommend!
Added nothing
I paired this with a sleeping bag rated for comfort at 30 degrees, and a sleeping pad with an R-value of 4.9. With temps in the high 20s/low 30s, this liner seemed to do absolutely nothing despite claiming to add 20 degrees to your bag. I spent a few hours shivering before adding my emergency bivy to the mix. Will be returning. Also worth noting that I am 5’2”, and this “compact” size was just barely big enough for me when cinching the top. This might work as a summer sleep option, but definitely do not count on this adding 20 degrees to your system. Also really wish these liners opened on the side like sleeping bags do - would make getting in and out a lot easier.
Works great!
I have a Kelty Comic 20 sleeping bag, rated for 19 degrees F, but my hunting trip this year was in the Flat Tops Wilderness area in CO, and the forecast said snow and temps down to 5 degrees F at night. I was using an REI Passage 1 tent as well. I didn't want to go out an buy a new sleeping bag, so I bought this liner in hopes to keep me warmer. I have to say, it worked great! We were in our tents before sunset, and I would open up some hand warmers and threw them in the bottom of my bag for extra heat. The Kelty 20, this sleeping bag liner, and the hand warmers kept me warm for aprx 9 hours each night despite onbe of the nights it getting down to -5 degrees! I would start to get a touch cold after 9 hours, and I am guessing that is when the hand warmers ran out of heat. All in all, I would say it works! It is pretty thin, but it is comfortable, and moves easily with me inside the bag!
Soft and Comfortable
[This review was collected as part of a promotion.] Material is soft and durable, easy to bring along on a camping trip. Fits snug in the little bag it comes in. Its like laying in a soft comforting cocoon, I cant wait to use it when I go camping. Its breath-able and yet keeps you warm at the same time.
