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Sea to Summit Reactor Plus Compact Thermolite Mummy Liner (Black/Orange)

  • Based on 335 reviews
Condition: New
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Availability: 11 left in stock
Fulfilled by marketbestchoice

Arrives Dec 25 – Dec 30
Order within 3 hours and 23 minutes
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Features

  • Fleece
  • First dual fabric sleeping bag liner. Adds overall warmth to a sleeping bag
  • 110g/m2 THERMOLITE panels in core body and foot areas for extra warmth
  • Compact, shorter design is ideal for women or anyone under 6 foot tall
  • Packs into its own Ultra-Sil stuff sack
  • Weight: 9.3 oz / 263 g. Dimensions: 72 in x 36 in (183 cm x 90cm)

Description

Sea to Summit stands for a culture of design perfectionists who develop ingenious, functionally beautiful products with an independent, free-thinking Australian attitude. We strive to create equipment that is nimble and light, but serious enough to deliver when called into duty. Gear that works just that little bit better, so you may find yourself inspired to take the less-traveled road more often. Ingenious. Functional. Reliable. Unconventional. Inspiring. The THERMOLITE Reactor Compact sleeping bag liner is the ideal choice for gram counters under 6 feet. It essentially uses a combination of two weights of THERMOLITE fabric, with the thicker more insulative being strategically placed across the torso and in the feet area. The hollow core fibers work like the fur of a polar bear in that they are incredibly insulating and trap heat effectively. This sleeping bag liner keeps your sleeping bag clean and is super easy to wash. It will bump up the warmth of your sleeping bag temperature rating considerably, depending on your environment and conditions. Read more THERMOLITE FABRIC The Reactor Series Sleeping bag liners and the foot boxes of the Women’s Trek, Talus and Latitude Sleeping Bags use hollow core THERMOLITE fiber to add warmth. Hollow cores fibers trap extra air for insulation (just like the hollow-cores of polar bear or caribou fur). Knitted THERMOLITE fabric is soft and stretchy and comes in three different weights: 80g/m² fabric used in the Reactor and the underside of the Compact Plus liners; a 110g/m² fabric which is used in the Extreme, and the core and foot box of the Compact Plus liner; and the Fleece, the warmest of all the fabrics. Read more Read more HIGHLIGHTS Packed Size Comparison: Similar to a small foam football Weight: 9.3 oz ≈ A bottle of sparkly non- toxic glue. Warmth: Adds up to 20°F to the temperature range of your sleeping bag. BONUS: Easy to wash and helps to keep your down bag cleaner for longer. Read more


Item Package Dimensions L x W x H: ‎6.57 x 6.02 x 3.94 inches


Package Weight: ‎0.29 Kilograms


Item Dimensions LxWxH: ‎72 x 35 x 0.4 inches


Item Weight: ‎286 Grams


Brand Name: ‎Sea to Summit


Color: ‎Red & Black


Manufacturer: ‎139


Part Number: ‎139


Model Year: ‎2019


Outer Material: ‎Polyester


Fill Material Type: ‎Down


Date First Available: August 20, 2009


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Dec 25 – Dec 30

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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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • It does work
I'm a backpacker that cares about weight. Recently I purchased a new quilt but it was defective. This left me with only a 30 degree for my last trip. I was expecting 20 degree nights, so I looked for options that would get me by till my new quilt came in. I purchased this Reactor Plus and a SOL Escape. Between the two, something had to help. I found the SOL compressed my bag more and I don't think it really helped much at all. The Reactor, on the other hand, did help very noticeably. I used it with my OV Atlas 30 degree bag on 17 degree nights, no extra base layers, just my normal sleeping pants and a long sleeve shirt. I was warm. My feet were warm. It was amazing how much of a difference it made. I put one arm over and one under to see if I could tell a difference. In a few minutes, it was a very clear difference. I wont say it gave me 20 degrees more warmth, but it probably did at least 10. It was enough to give me a good night sleep with otherwise inadequate gear. I did have extra clothes to wear in case the two bags did not help enough, but didn't need them. I do recommend it, even though the price is way more than I think it is worth. ... show more
Reviewed in the United States 🇺🇸 on January 20, 2020 by B. Andrews

  • Added warmth in a small package
Small lightweight package for the added warmth. Worked as intended.
Reviewed in the United States 🇺🇸 on February 22, 2022 by Stew

  • it feels comfortable and was warm enough for a summer night
I am going on a trip soon so will have a chance to field test this sleep sack. I did try it as an only blanket on my bed ,it feels comfortable and was warm enough for a summer night. Camping in the North Cascades this August will be the real test so i will have more comments then. Additionally, I am going on a longer trip this fall where camping will be a possibility so more opportunities to test out the warmth factor. The compact size will be nice when I go on flights and I will unroll it for use as a lightweight blanket. Nov. 4 2017 I went on my trip and for two months I made frequent use of this sheet. Too often, the blankets in hotels were too hot so this sheet set was a good alternative to keep the draft off while allowing me to be covered and not too hot. ... show more
Reviewed in the United States 🇺🇸 on June 30, 2017 by happy traveler

  • Works
This was used to offset the temps of a sleeping bag that would fall short of windy winter mountain temps. Used nightly for more than a week I am glad I bought it. I wouldn't count on it for the full advertised temp ratings as others mentioned but its good for 50% of its advertised claims. I had a 32 degree lafuma down sleeping bag with this and was warm in 21 degree weather. Not just warm but comfortable. I also used the liner as a sort of blanket for hanging out around camp and it worked out just fine. The only things I can think of about this that would be negative is it generates a lot of static electricity when getting in and out. I could actually see the sparks when sliding in and out. This has the potential to damage any electronics you may have with you on your voyage. The other is cost. I dont feel this is a value more so than a premium price and a value product. ... show more
Reviewed in the United States 🇺🇸 on December 30, 2015 by JWill

  • Toasty
This has definitely made a difference on the colder nights. I haven't done the scientific tests with confirming temp difference with or without vut before I purchased, would sleep with 2 layers and hand wamers in bag and still feel chilled. After purchasing...only base layer and still had hand warmers and felt quite toasty! Very light weight, able to stuff in sack with sleeping bag. ... show more
Reviewed in the United States 🇺🇸 on December 20, 2020 by Stacey M.

  • Great liner, note the length before buying!
This liner is great! Kept me very cozy in 25 degree weather when added to my (old) 25 degree bag. Definitely note this one is “short”. I would recommend the taller one if you’re over 5’6”. (I’m 5’7” and it worked and wasn’t super cozy, it’s just hard to snuggle in all the way which is important if it’s cold.) ... show more
Reviewed in the United States 🇺🇸 on January 3, 2020 by Susannah

  • It works, would by again.
I would purchase again! I was skeptical after reading many reviews of liners in general, but decided to give the Sea to Summit liner a try. I was also skeptical when it arrived, it is very light and thin. However, I tested it on an overnight trip with a Kelty 20 degree down bag, in 18- 20 degree temperatures, ...and during the night, I had to shed clothing layers. It will be in my pack on all cold weather trips! ... show more
Reviewed in the United States 🇺🇸 on March 19, 2019 by KayakOC1

  • An absolute life saver/must have if you're going to push the downward limits of your sleeping bag.
OMG... does this make a HUGE difference. It really did increase my sleeping bag's rating probably a good 15 degrees and keeps the cold silkiness of the polyester away from your skin. Also helps with keeping your sleeping bag dry/clean. I will never go w/out again. Worth every penny and more! 10/20/15 I just got back from a backpacking trip and ended up lending this to a fellow camper. Her bag was only rated to 30 and the temp dipped into the mid 20s over the weekend. She spent the first night shivering, even in her wool clothing. I let her use this liner and she said she was able to sleep with only a thin layer of clothes on. This was a women who was about 5'4" and probably only weighed about 100lbs. ... show more
Reviewed in the United States 🇺🇸 on October 14, 2015 by Abigail Fry

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