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Sea to Summit

Sea to Summit Reactor Insulated Sleeping Bag Liner

    • Based on 1,992 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Wednesday, Dec 25
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Style: Extreme (83 X 35)


Features

  • Outer fabric material: 100% polyester
  • Imported
  • Insulated sleeping bag liner adds extra warmth and personal hygiene to any sleeping bag
  • Reactor Extreme features heavier weight Thermolite throughout and adds up to 25F degrees
  • Thermolite hollow core insulation is lightweight, soft and comfortable with stretch knit construction
  • Mummy shaped with toe-box, draw cord hood and included stuff sack
  • Extreme (M) Dimensions 83 x 35-inches; packed size 6.5 x 4.5-inches; weight 14oz

Description

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 knit construction also gives the liners a degree of stretch. Available in four different weights, Reactor technical liners effectively make your existing sleeping bag warmer and more versatile. The original Reactor is the lightest and most compact and can add up to 14F degrees of warmth. The Compact Plus is designed for women with a shorter length and includes heavier layers of Thermolite in the toe box and torso areas for extra comfort. The Reactor Extreme comes in two lengths and has heavier weight Thermolite throughout, extending the range of a sleeping bag up to 25F degrees. The Reactor Fleece is warm enough to use on its own, adding up to 32F degree while still packing down smaller than most fleece blankets. All Reactor liners are mummy shaped with a toe-box, feature a drawcord hood and include a stuff sack. Reactor Thermolite sleeping bag liners are lightweight, compact and easy to clean.


Brand: ‎Sea to Summit


Color: ‎Red


Shape: ‎Mummy


Seasons: ‎Evergreen


Temperature Rating: ‎Extreme


Material: ‎Thermolite®


Fill Material: ‎Down


Product Dimensions: ‎83"L x 35"W


Closure Type: ‎Drawstring


Item Weight: ‎399 Grams


Outer Material: ‎Nylon


Fabric Type: ‎Outer fabric material 100% polyester


Size: ‎90 x 120 cm cm


Item Package Dimensions L x W x H: ‎7.76 x 4.57 x 4.53 inches


Package Weight: ‎0.4 Kilograms


Item Dimensions LxWxH: ‎83 x 35 x 0.4 inches


Brand Name: ‎Sea to Summit


Warranty Description: ‎Manufacturer guarantee against defects in materials or workmanship for the lifetime of the product


Model Name: ‎Thermolite Reactor Extreme


Suggested Users: ‎Unisex


Number of Items: ‎1


Manufacturer: ‎Sea to Summit


Part Number: ‎AREACTOREXT


Model Year: ‎2014


Style: ‎Extreme (83 X 35)


Fill Material Type: ‎Down


Date First Available: October 1, 2001


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Dec 25

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Low quality seams
Style: Extreme (83 X 35)
Review Image by Brandon Scott
You would think for a big name brand that they'd have better quality construction. Just opened up the liner to test it out at home and there's already a big hole in the footbox. UPDATE: I originally reviewed this about a week and a half ago after receiving it in the mail. I was never contacted by Sea to Summit about the issue. Now I'm all about honest reviews and that's why I posted the review in the first place. But I also like to fix things and although super annoying and frustrating that it came with a torn seam right out of the package, I fixed it myself. Just a little basic sewing. Shout out to Youtube! I used this for the first time this past weekend. I have the Teton Tracker sleeping bag that I use in my hammock and I purchased this to go along with it. The very first night out it ended up raining and sleeting and winds were about 20mph. I had not broken out the liner yet because I wanted to push the limits of my sleeping bag and see how well it would do. About halfway through the night though I had to reach up and grab the liner off of my ridgeline because I started getting cold in my bag. I was in my sleeping bag in my hammock with an underquilt. Temps this night were dropping to the low 20s F (approx. -7 to -4 degrees C for my metric peeps) and with the windchill is was easily in the teens (-12 to -7 degrees C). My sleeping bag is rated down to 5F (-15C) but for anyone who understands sleeping bag ratings, that's what you can survive at, no what you'll be comfortable in. I also didn't have the proper underquilt for my hammock since it was rated down to 40F I believe. So needless to say, I started getting a tad bit chilly as the night went on and the temp kept dropping. This is where some other issues with this liner arise. If you've read the Q&A section on this product or any of the reviews you'll have figured out that there is only one opening into this thing. So imagine trying to unravel a 7ft (2.13m) tall 100% polyester lining thats super elastic, all while trying to stay in your hammock in your sleeping bag and out of the rain/sleet. It didn't work out too well. I ended up saying screw it and just covered up my torso with the liner. EVEN JUST COVERING UP MY TORSO I WAS SIGNIFICANTLY WARMER. Just that extra layer in my sleeping bag made quite the difference. The second and third nights the weather was still very cold, but the wind was just a slight breeze and it was clear skies. Both of these nights I actually got into the liner completely before getting into my sleeping bag in the hammock. I stood on a piece of plastic underneath my hammock (where I set my boots) and stepped into the liner, bringing it up to my armpits before actually getting into my sleeping bag in the hammock. Still not the easiest thing to do because of course the liner isn't stapled to me so it doesn't stay still. The BIGGEST drawback to this liner I believe is having just the one opening. Obviously if you're in a tent, although still inconvenient, this isn't that big of a deal. But if you're hammock camping, this is my heads up to you. BUT, aside from the hassle of getting into it and having a torn seam out of the package (still salty about it), I will say that this liner DID add significant warmth to my sleeping bag. As other reviews have said I do not think that it adds the 25F (15C) that they claim. But it does add significant warmth and I was quite toasty the second and third nights on this trip. Overall, if you're looking for liner to add some warmth to your bag it's probably safe to say that this will do the trick. Just be cautious of the three things that I have mentioned: 1) Quality of the seams (inspect them as soon as you get it!) 2) Pretty positive it will not add the 25F (15C) that they claim. Probably more along the lines of 10 F (give or take) 3) Only one way into this thing Some quick PROS that I'll add are the packability, weight, and warmth. After sewing the seam on my own I will continue using this liner. As I said, I am happy with the warmth it added. I will post an update down the road after I get some more use out of it! But since it did keep me from freezing my but off the second two nights I'm going to add another star to my rating, making it 3 stars. ... show more
Reviewed in the United States on January 11, 2019 by Brandon Scott
    • Didn't have much of a purpose for me
Style: Extreme (83 X 35)
The material is soft and comfortable, and it does help to warm a bit. However, it doesnt hold warm air in, so it's not very useful on its own over a blanket. It's lightweight, but if used to make a bag warmer and weight is a concern then just getting a warmer bag makes sense. I was hoping to use this alone in some high 50s low-60s overnight Temps, and it can't do that. When I hike I care about my pack weight a lot, so getting a cooler bag (vs the 35 degree rated one I have) ended up making more sense for my needs. I could see this being a good product for camping, where you're not hiking with everything on your back, and you just need to warm up a bag. ... show more
Reviewed in the United States on September 13, 2022 by PopnFresh
    • Seems nice
Style: Extreme (83 X 35)
Shipped fast looks well made for what it is . Haven't been able to use waiting for colder weather .
Reviewed in the United States on September 9, 2022 by Tim
    • VERY SPENDY: Fills a unique and important niche.
Style: Extreme (83 X 35)
I paid such a ridiculously high price for this product that I am too ashamed and embarassed to admit it, to you. I did, however, decide to purchase it, anyway, despite the high premium. Here is why ... So, I have constructed a lightweight 3-season system, for Central Texas, which does get "very" cold, at unpredictable intervals, throughout the late-fall to early-spring "trimester". Central Texas is Hill-Country ... Lots of steep ridges and canyons, all bunched together and there is lots of climbing involved and major weather fronts converge, in this region, manifesting all sorts of conditions, sporadically and unpredictably. My sleep-system consists of ONE G.I. Gortex Bivy-Bag and one SnugPak compact and lightweight "JUNGLE" bag (with integral bug-net), ... In order to augment this basic system, I also carry a VERY light and VERY compact Adventure Medical ThermoLite 2.0 Reflective Emergency Bivy AND ... YES ... This (equally ultra-light and compact) ThermoLite Reactor Extreme Mummy Liner. In colder weather, I may carry an additional silk or fleece bag liner. *** COST JUSTIFICATION *** These augmentation components fit in your open hand, and are smaller than a standdard roll of toilet-paper (and are a little lighter.) This allows for a very light, compact, and highly mobile and flexible sleep system that can "stretch" your temperature tolerance by (very hopefully) 25 to 30 degrees, F. I also carry a Short RidgeRest (aluminized) closed-cell pad, which is shorter and narrower than most pads. To be honest, I do not believe that these (ThermoLite) ultralight options perform to their optimistic claims, of 15 degrees for the thermal bivy and 25 degrees for the Reactor-Extreme bag liner ... Again, used together, properly, ?? ... 30 degrees of boost is the most one could hope for, and is probably overly optimistic ... I would expect to get slightly better than 20 degrees using BOTH thermalite components, if the temps were below freezing. Anything that weighs less than a roll of toilet-paper and is smaller, that can boost my sleep comfort (and survival envelope) by ANY significant amount MUST be worth spending a bit "more". ... And ... I sure DID ! Sorry ... no anecdotal gripes, as of yet ... I try not to use this resource any more than necessary. If I KNOW ... IN ADVANCE ... That it will be cold, then I will pack my USGI-ECWS-IMSS which is 12 pounds and will handle anything Texas can throw at me (any time). Hope this helps. ... show more
Reviewed in the United States on June 3, 2012 by Studio Gear Head
    • Great material!
Style: Extreme (83 X 35)
Great buy. I was surprised the bright red didn't bleed out in the wash or on my skin. It was a great size both in length (I'm 6ft) and in width (enough for 2 average people to fit inside). The liner made a huge difference between 15-35f and as a stand alone in 60-70f (for when you want something but a sleeping bag is to warm). ... show more
Reviewed in the United States on July 7, 2022 by Tj
    • Great with my quilt
Style: Extreme (83 X 35)
Great addition to my sleep system outdoors!
Reviewed in the United States on June 18, 2022 by Kickin' up Dirt Somewhere

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