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Sea to Summit

Sea to Summit Reactor Insulated Sleeping Bag Liner

    • Based on 1,872 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives May 29 – May 31
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Style: Extreme Long (92 X 35)


Features

  • 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 (L) Dimensions 92 x 35-inches; packed size 7 x 5-inches; weight 14.9oz

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: One Color


Shape: Mummy


Seasons: All Seasons


Temperature Rating: Extreme


Age Range (Description): Adult


Sport: Multi-Sport


Material: Fabric


Fill Material: Thermolite


Product Dimensions: 93"L x 35"W


Brand: ‎Sea to Summit


Color: ‎One Color


Shape: ‎Mummy


Seasons: ‎All Seasons


Temperature Rating: ‎Extreme


Age Range (Description): ‎Adult


Sport: ‎Multi-Sport


Material: ‎Fabric


Fill Material: ‎Thermolite


Product Dimensions: ‎93"L x 35"W


Closure Type: ‎Drawstring


Item Weight: ‎450 Grams


Size: ‎Long


Item Package Dimensions L x W x H: ‎7.36 x 5.28 x 4.57 inches


Package Weight: ‎0.47 Kilograms


Item Dimensions LxWxH: ‎36.61 x 13.78 x 3 inches


Brand Name: ‎Sea to Summit


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


Suggested Users: ‎unisex


Manufacturer: ‎Sea to Summit


Part Number: ‎7


Model Year: ‎2017


Style: ‎Extreme Long (92 X 35)


Fill Material Type: ‎Thermolite


Date First Available: January 18, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: May 29 – May 31

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

    • Pleased with the item but…
Style: Extreme (83 X 35)
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 trip you might be rolling a little grubby. Turns out my favorites 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 bikepacking trip on warm nights. It also works well as a bag protector with added warmth to my -20° winter bag. Allowing you to sleep without base layers if that’s your thing. It does not however extended the range of my 20° bag. So if you’re thinking to buy this to push your 20-30° bag to a 0° then I suggest putting them money towards a proper 0° instead. Sleeping outside in zero degrees is really cold and while this helps a bit, it doesn’t make up for the right gear for the job. ... show more
Reviewed in the United States on April 23, 2023 by Amazon Customer
    • Very surprised
Style: Extreme (83 X 35)
It is very thin and lightweight. At first I didn't think it would do very much and regretted not buying something heavier. It worked surprisingly well. Lined a zero degree bag in 20 degree weather. And was very comfortable.
Reviewed in the United States on May 3, 2023 by Timothy McWilliams
    • Warm while climbing the Kilimanjaro
Style: Extreme (83 X 35)
The highest I used it was at 16,000 feet on the Mount Kilimanjaro in Tanzania. It does bring an extra warmth to the sleeping bag
Reviewed in the United States on May 2, 2023 by Amazon Customer
    • works great. fast ship
Style: Fleece (79 X 28)
works great. fast ship
Reviewed in the United States on May 11, 2023 by MICHAEL GREER
    • Low quality seams
Style: Extreme (83 X 35)
Review Image by Brandon Scott 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 Brandon Scott
    • Very thin and lightweight
Style: Extreme (83 X 35)
It worked well. I'm not sure about adding a full degree increase mentioned but it will help for sure. Also can use as a stand alone in warm weather which is nice as it is small though to fit into a pants pocket. I leave it inside my primary bag and pack it like normal so it's always ready to use
Reviewed in the United States on March 26, 2023 by H. Hursky
    • Expensive but high quality
Style: Regular (83 X 35)
I went on a substantial trip about 70 miles into the Utah desert in early November. I discovered that I had COVID on the first night, when I woke up with a fever, sweating and shivering uncontrollably. My sleeping setup has been fine for similar conditions in the past, but when you mix in a fever, you get sweating and hypothermia even with proper gear. I managed to stuff this liner into my bag after waking up and, despite it effectively feeling like just t-shirt material, the bit of additional dry insulation made a huge difference and I was able to comfortably sleep through the rest of the night. Not sure if I would have actually died if I didn't have this liner, but the thought has certainly crossed my mind. ... show more
Reviewed in the United States on January 9, 2023 by George T.
    • Very soft and warm
Style: Fleece (79 X 28)
With my 20° quilt and this liner I slept comfortably at 19degrees. Lightweight and a nice add on for comfort
Reviewed in the United States on March 12, 2023 by Sean hissong

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