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Sea to Summit

Sea to Summit Reactor Insulated Sleeping Bag Liner

    • Based on 50 reviews
Condition: New
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This item's return window has been extended for the holiday season: Returnable until Jan 31, 2025

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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Nov 25
Order within 17 hours and 7 minutes
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Style: Extreme Standard (85 X 31.5)


Features

  • thermolite
  • Imported
  • Insulated sleeping bag liner adds extra warmth and personal hygiene to any sleeping bag.
  • Thermolite Pro technology using knitted, hollow-core fibers and absorbing infrared ceramic pigments to reflect your body's heat back to the wearer for enhanced warmth and comfort
  • Drawcord footbox can be opened or closed for optimal comfort and integrates perfectly with the footbox of our Free-Flow Zip system in select 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

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 stretch- knit fabric provides optimal comfort, and ensures the Reactor fits any sleeping bag. Additionally, the drawcord footbox offers plenty of ventilation and the versatility of walking around camp while still wearing your liner. Available in three different weights, Reactor technical liners make your existing sleeping bag warmer and more versatile. The Regular Liner uses hollow-core Thermolite Pro fabric with infra red-absorbing ceramic pigments and Thermolite EcoMade fibers. This lightweight fabric adds up to 14F of warmth to your sleep system. The Extreme Liner features a thicker hollow-core Thermolite Pro fabric to add up to 25F of warmth to your sleep system. The Fleece Liner employs hollow-core Thermolite Pro fibers in a grid-pattern to deliver our warmest sleeping bag liner which adds up to 32F of warmth to your sleep system.

Brand: Sea to Summit


Color: Orange


Occupancy: 1


Shape: Mummy


Seasons: 3 Seasons or Winter


Temperature Rating: Up to 25F increase in sleeping bag warmth


Sport: Backpacking, Camping, Hiking


Special Feature: Drawcord Footbox


Material: Thermolite


Fill Material: Thermolite


Brand: ‎Sea to Summit


Color: ‎Orange


Occupancy: ‎1


Shape: ‎Mummy


Seasons: ‎3 Seasons or Winter


Temperature Rating: ‎Up to 25F increase in sleeping bag warmth


Sport: ‎Backpacking, Camping, Hiking


Special Feature: ‎Drawcord Footbox


Material: ‎Thermolite


Fill Material: ‎Thermolite


Closure Type: ‎Drawcord


Item Weight: ‎0.85 Pounds


Outer Material: ‎thermolite


Fabric Type: ‎thermolite


Item Package Dimensions L x W x H: ‎8.19 x 7.6 x 4.37 inches


Package Weight: ‎0.41 Kilograms


Item Dimensions LxWxH: ‎8.46 x 5.91 x 2.95 inches


Brand Name: ‎Sea to Summit


Country of Origin: ‎China


Manufacturer: ‎Sea to Summit


Part Number: ‎ASL031071-190804


Style: ‎Extreme Standard (85 X 31.5)


Fill Material Type: ‎Thermolite


Date First Available: January 24, 2024


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Nov 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

    • Cozy!
Style: Fleece Standard (85 X 31.5)
Review Image by Bekkah Bekkah
Review Image by Bekkah Bekkah
Bought for my Virginia hike at the end of November. I wanted lighter weight and someone to keep my body heat inside. I've tested in my hammock at as low 35 degrees and has kept all cold air from flowing it! It's affordable and quality is great! Also, the pooch joins me on our nightly hammocking and he loves the warmth of it as well! ... show more
Reviewed in the United States on November 11, 2024 by Bekkah Bekkah
    • Great product
Style: Extreme Standard (85 X 31.5)
I’m a cold sleeper so I was a little worried when the temp dropped way lower than seasonal normals on my last backpacking trip. I have a 20 degree bag with temps at 36. I purchased this liner and actually woke up sweating! Not only that, but it’s functional- I wore it all morning since your arms are out and you can raise it to a comfortable level on your legs. I would buy again and can imagine using only this during the summer! ... show more
Reviewed in the United States on October 23, 2024 by Amanda E.
    • Very Happy With Liner
Style: Extreme Compact (78 X 31.5)
The material feels great. I love the opening at the bottom and the option to make it “wearable” at the top. It gave me a few extra degrees of warmth. It kept my sleeping bag cleaner.
Reviewed in the United States on September 23, 2024 by Arcadian Dreamer
    • Nice and warm
Style: Fleece Compact (78 X 31.5)
I got this for two reasons. First, backpacking in the mountains at around 11,000 feet in Utah there's always a risk it can get in the 30s at night. It's VERY light at .85 lbs so hanging it on the outside of your backpack isn't an issue in my opinion. Second, I wanted something that I could slip on at night sitting around the the fire. While this works it doesn't fit around my neck and arms as comfortably as I would like. It is really warm, especially for how thin it is, so that's great. I'll keep using it, it's a nice product. I just wish the fit was better... ... show more
Reviewed in the United States on August 2, 2024 by A. McKinnon
    • Warm, Light, Great Features! - Extreme Standard
Style: Extreme Standard (85 X 31.5)
Extreme Standard I really wish I would have been able to try every option for this. I had a hard time debating on if I wanted the warm/smaller/lighter options vs. the hot/heavier/larger options. Ideally, I would have all the options available to pick and choose for each individual trip. I decided the Extreme option would fit the majority of my use cases. -Sizing: at 6’2” I required the standard sizing over the compact sizing. If I recall correctly the details specified anyone 6’1” or over would need the standard sizing. At this height I’m used to buying the extra length options anyway. -Warmth: In Arkansas I’m still a couple months away from getting some real use out of this. Just slipping it on in the house, it appears that it will preserve some of that much needed heat on a colder night. Yes, we do get occasional cold spells in Arkansas where extra warmth is needed. I’ve even seen and slept in some rare sub-zero temperatures, but had to alter plans because I was ill equipped for it. The specs say this will add up to 25 degrees of warmth. The Sea to Summit site specifies the added warmth relies on multiple factors including your ground and sleeping bag insulation. In other words if you are wanting optimal performance out of this, pair with other quality gear. -Softness: This will be very soft and comfortable, but honestly if I’m using this I probably already have a moisture wicking compression layer on. The soft hood will be nice. -Features: I love how the arms are out. I already have a bit of claustrophobia I fight through sleeping in a mummy bag, and this allows me a little more movement in my sleep while keeping my core warm. Options to have the feet in or out are great as well. Both of these features also allow for additional warmth while just hanging out at camp. -Space/Packing/Weight: This does not add a lot of space to the bag, and is easy to get in the sack. It is also lightweight so you will not be adding much to your bag weight. Everything seems to align with the specs. -Materials: Everything in this feels like good quality materials that I’ll be able to trust in those vulnerable nights. Overall, this is a quality product and everything you would expect to come from the Sea to Summit brand. I’m very happy with my purchase, and plan to put it to good use later this year. ... show more
Reviewed in the United States on September 10, 2024 by A. Haney
    • Summer, Winter, It Doesn't Matter!
Style: Extreme Compact (78 X 31.5)
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
Review Image by Woodland Wanderer Woodland Wanderer
The media could not be loaded. I am a fan of Sea to Summit products in general, and the Sea to Summit Reactor Insulated Sleeping Bag Liner is no exception. In fact, it is my favorite addition to my kit to date! This thing is so versatile! I have used the Sea to Summit Comfort Blend Sleeping Bag Liner and the Sea to Summit Silk Blend Sleeping Bag Liner, but neither include the awesome features of this Reactor. Don't get me wrong, those are great products, but every time I use them I find myself wishing for the features the Reactor has. So, what is so great about this liner versus the others? I will break these features down for you: 1.) Versatility - this liner is warm enough to be a summer alternative to carrying a sleeping bag. If you have ever been sleeping in 90+ degree night temperatures with a humidity and bugs, then you know that a sleeping bag is just too much, but you want something. This liner is perfect for that. You can regulate body temperature by sticking your feet and arms out, or snuggle up inside the bag if it gets a little chilly during the night. In cold weather, it adds comfort to any sleeping bag and keeps you from having the sleeping-bag-night-sweat feeling. 2.) The flexibility for temperature regulation. I am one of those people that likes to keep my feet in the air, and I like to be able to move my arms. At the same time, I want something covering my core and like to snuggle in. This Reactor is designed to allow for all of that. I also roll a lot during the night, and being able to have my feet and arms out of the liner helps keep me from getting all twisted up. The snaps and draw cords are high quality, but do keep in mind that if you yank on the snaps with the liner fabric, you are likely to have a very short snap life. Treat them right and they will last a lifetime. 3.) Have I mentioned the ability to open the bottom of the liner and put my feet out? Yeah, a feature in itself. I can cook breakfast, wear this to go to the bathroom at night, get dressed inside it, snuggle by the campfire, and just generally do whatever needs to be done with this liner on. I LOVE it!!!! By now I am sure you realize I am a true fan of this liner. I simply cannot find anything I don't like, honestly! If anything, the weight in winter could be a negative, but considering the warmth and features, that is very worthwhile and I don't know of another product that comes even close to the features, comfort, or weight for what this offers. I think this should be a foundational purchase for every backpacker at least, but probably also for anyone who enjoys camping. Do yourself a favor and just buy it. ... show more
Reviewed in the United States on August 4, 2024 by Woodland Wanderer Woodland Wanderer
    • Provides some warmth
Style: Extreme Standard (85 X 31.5)
Do not use this to convert at bag to a lower temperature rating, it does not provide enough warmth to make a 20 deg bag a 0 degree bag.
Reviewed in the United States on September 22, 2024 by Chris C

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