Sea to Summit  Reactor Thermolite Sleeping Bag Liner

$69.95to $74.95

Powered by Thermolite® Pro fabric that uses an innovative infrared technology, the Sea to Summit Reactor Thermolite sleeping bag liner provides exceptional warmth, versatility and freedom of movement.

Color: Sulphur Yellow
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$74.95
$69.95
Quantity
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Features

  • 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 knit, 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
  • Knit 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

Technical Specs

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: 10 ounces

Compact: 9.5 ounces

Sustainability

Contains recycled materials

Reviews
190 reviews with an average rating of 4.4 out of 5 stars

Ratings Snapshot

Product Rating

131 out of 143 (92%) reviewers recommend this product

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Average Customer Ratings

Ease of Use

Difficult to useVery easy to use

Product Weight

LightweightHeavy

Most Helpful Favorable Review

5 reviews with an average rating of 4.0 out of 5 stars
roasty toasty
ecogyrl
12 years ago
Received free product
i've only had one opportunity to use this since i just purchased it, but so far, so good. we camped in 20 degree weather and my husband had to shed his after getting too warm (we also have 0 degree bags, but they are ~15 years old) so i doubled up and had the best camp sleep ever. he would likely leave a less glowing review since he is a human radiator and also like to turn cartwheels in his sleep and found the liner a bit too confining. typically, we zip our bags together which gives him a bit more room to kick me in his sleep, however, since these are super light, there are no zippers to combine them so he was additionally confined to his own sleeping bag (probably another reason i slept so good!). short story long - i loved the liner, but he would probably have a different story.
ecogyrl
157 people found this review helpful

Most Helpful Critical Review

5 reviews with an average rating of 3.0 out of 5 stars
Sea to Summit Reactor Thermolite liner
hikerchick
11 years ago
Received free product
I find that sleeping bag liners, for the most part, don't work well for me. Using one would be effective in keeping a bag clean, but I'm confronted with the problem of getting tangled up and the awkwardness of getting in and out of my sleeping bag. However a liner, like the Sea to Summit Thermolite, can be a good addition to adding more warmth when needed without paying the price of a warmer sleeping bag. I think the increased warmth of 14 degrees on the light weight liner that I purchased maybe optimistic, but I felt it performed well enough in turning my 41-degree rated sleeping bag to closer to a 31-degree bag during an early October overnight wilderness trip where the night temperature pushed the limits of my sleeping bag. Liners are intended to be used on the inside of a bag. All though, for those who are bothered by the problem of getting tangled up and need the gain of a little additional warmth, try slipping it over the outside of your sleeping bag like a bivy sack.
hikerchick
32 people found this review helpful

Customer Images

isaiahh12
Rated 5.0 out of 5 stars

Lightweight & Warm!

1 year ago

[This review was collected as part of a promotion.] I was very surprised by how much heat this held in from my body heat. It's a very thin material, but it's soft and slightly fuzzy. It was roomy and comfortable. If it was a thicker material, I think I would have felt restricted. It fits in my sleeping bag very easily. I like how you can cinch in the top and bottom to keep the heat from escaping. Even though it's thin, it's pretty durable. It's slightly stretchy, which helps with durability and comfort. It's was very easy to fold and roll back up to fit into its original bag. If you're looking for a little extra warmth added to your sleeping bag, this would be a great liner for you!

Originally posted on influenster.com
Chloesway
Charleston, SC, United States
Rated 5.0 out of 5 stars

Best thing ever!

10 years ago

I purchased this to give me some extra warmth (I run cold) in Patagonia, and I am so glad I did! First, I was surprised by how thin and soft it is. Really soft. I used it a few times while hanging out on the couch at home, and it truly does keep you warm. If it's really cold, you need to cinch it up properly (I rarely did) and you'll be roasting in no time. I ended up taking it on the long flights with me, and using it as an airplane blanket. Frankly, I also planned to use it as a shawl if I needed it while hanging out in the evenings. It's amazing. I'm not putting it away with the camping gear, I'm keeping it handy as a spare blanket at night to go star gazing!

Yes , I recommend this product
Helpful?
bekbot
Los Angeles, CA
Rated 5.0 out of 5 stars

Magical

15 years ago

I join the ranks of satisfied reviewers. Writing this review on behalf of my sister... we trekked for 3 months in a Himalayan winter that spilled into summer. Since I joined the trek late and had heard my sister was struggling with the cold, I brought her this liner to warm up her sleeping bag. I haven't seen her so in love with a fabric since her childhood blankie. She even opted to use it once we returned to town and checked into a guesthouse. I was skeptical to buy this at first because of the price, but seriously, what's in this thing? Magic? Worth the dough if you're into cozy factor.

Yes , I recommend this product
Helpful?
Work Earn Buy
Cary, NC
Rated 4.0 out of 5 stars

Compact and versatile

12 years ago

I bought this bag for several reasons, but primarly for a lightweight and warm weather bag. I'm in NC and do most camping in NC and it's warm here most of the year. I bought this bag/liner and have so far only used it alone. And that's what I wanted it for. It's cozy to sleep in and just right for warm weather camping. In "cool" weather, I've used it with a space blanket over it and was fine too. I haven't yet tried as a bag liner, but based on its solo performace I'm sure it will add a few deg of warmth to my mummy bag. I also keep it in a survival pack in my trunk when not camping.

Yes , I recommend this product
Helpful?
snowbunny
western pa
Rated 5.0 out of 5 stars

a must-have travel item

15 years ago

I have only good things to say about this liner! I'm a small girl who gets cold easily and this is a wonderful item to own if you camp or travel. It only weighs a few ounces, is easily stashed in its own little stuff sack, and has so many uses. I've actually pulled it out on international flights (like I said, I'm always cold) and I've used it in my bed when staying in hostels or hotels with questionable cleanliness. It was perfect when backpacking in Japan where temps reached 110 - something to cover myself but not get overheated. Washing/drying is a breeze, too. Highly recommended!

Yes , I recommend this product
Helpful?
Alex
Rated 4.0 out of 5 stars

Fits your sleeping pad!

3 years ago

I bought this at the members sale and found out later you can fit an entire Nemo tensor long wide inside it and synch it up so it doesn’t come off! Now I won’t have to sleep directly on the pad when it’s hot out and dirty it up and the liner is also softer than the pad material! Does not look like it puts a strain on stretching the foot box, still within the elastic region of strain. Originally bought it to add some warmth to my 20 degree sleeping bag and as something I can wash without dirtying my bag. Have not used sleeping yet, but will soon in April. Double whammy!!

Yes , I recommend this product

Ease of Use

Difficult to useVery easy to use

Product Weight

LightweightHeavy
Helpful?
H Diddly
Denver, C
Rated 5.0 out of 5 stars

Key piece of kit

5 years ago

I sleep cold like most women. This liner makes my cheap summer mummy bag work in shoulder season, and will make my new 0 degree bag a true winter option. In the past 8 years, I've used this as a liner in down to 0 degree weather with a rental bag, with my husband's borrowed 0 degree bag, and with my own bag. It's soft, comfortable, breathes, warms, and works fine with or without socks and layers. I've used it in hostels and guesthouses. I've also used it summer camping on its own. I machine wash it, air dry, and it is the same as when I got it. I asked for it one holiday and it's still one of the better things I listed!

Yes , I recommend this product
Helpful?
optionalfield
Kennesaw, GA
Rated 4.0 out of 5 stars

Great purchase!

11 years ago

I recently took a trip to Yellowstone and did some backcountry camping. The temperatures got down to the mid/low thirties overnight and I knew from previous (and uncomfortable) experience that my sleeping bag wouldn't keep me warm enough. I purchased this liner to supplement my sleeping bag and it totally worth the money. It's very thin and lightweight so I was concerned about its effectiveness, but I was incredibly comfortable and warm all night. The fabric is also very soft and cozy and added minimal weight to my pack.

Yes , I recommend this product
Helpful?
ecogyrl
berea, ky
Rated 4.0 out of 5 stars

roasty toasty

12 years ago

i've only had one opportunity to use this since i just purchased it, but so far, so good. we camped in 20 degree weather and my husband had to shed his after getting too warm (we also have 0 degree bags, but they are ~15 years old) so i doubled up and had the best camp sleep ever. he would likely leave a less glowing review since he is a human radiator and also like to turn cartwheels in his sleep and found the liner a bit too confining. typically, we zip our bags together which gives him a bit more room to kick me in his sleep, however, since these are super light, there are no zippers to combine them so he was additionally confined to his own sleeping bag (probably another reason i slept so good!). short story long - i loved the liner, but he would probably have a different story.

Yes , I recommend this product
Helpful?
paulieboy
Cranberry Lake, NY, United States
Rated 5.0 out of 5 stars

Expands my temperature range

8 years ago

Bought this to extend my 20° rated bag. It worked amazingly well. I was toasty warm in 10° weather.

Yes , I recommend this product
Helpful?
1 - 10 of 190 Reviews

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