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Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner

    Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner

    This Sea to Summit Reactor Extreme mummy bag liner adds a few degrees of warmth and extends the life of your sleeping bag. See details

    • $66.95

    Item # 797114

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    This Sea to Summit Reactor Extreme mummy bag liner adds a few degrees of warmth and extends the life of your sleeping bag.

    Product size and color

    This Sea to Summit Reactor Extreme mummy bag liner adds a few degrees of warmth and extends the life of your sleeping bag.

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    This Sea to Summit Reactor Extreme mummy bag liner adds a few degrees of warmth and extends the life of your sleeping bag.

    • Constructed of insulating Thermolite® fabric, a hollow-core, breathable fiber that provides extraordinary warmth for its weight
    • Adds up to 25°F of warmth to a sleeping bag; can also be used as a summer ultralight sleeping bag
    • Liner helps keep the inside of your bag clean, saving it from the wear and tear of washings
    • Drawcord hood with mini cordlock cinches around face to hold warmth in
    • Mummy shaped liner features a 3D footbox providing plenty of room for feet
    • Comes with a lightweight Ultra-Sil™ stuff sack


    Item 797114

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    Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner Specs
    Best use
    Up to 25 degrees
    Up to 14 degrees
    3 x 5 inches
    84 x 36 inches
    14 ounces
    0.39 kilograms
    Sleeping bag shape
    Added warmth (F)
    Added warmth (C)
    Stuff sack size
    Weight - metric

    Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner

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    Sea to Summit Thermolite Reactor Extreme Mummy Bag Lineris rated4.0833out of5by24.
    Rated5out of5byfromSaved my bacon23deg zissou bag, got wet...didn't have time to fluff properly. Caught in freak cold snap on top of GA mountain on AT...13degrees + hail/snow. Bag had lost some of it's insulating ability and I'm convinced this liner saved my butt. I had all of my dry layers on ( had rained all day ) w/bag but was shivering badly. Used liner, cinched it up tight around my shoulders ( key ), and sealed mummy bag. Cold, but got through night. Without this...I probably would have been hypothermic. It's lightweight insurance that you can keep in the bottom of your sleeping bag when you need it, and just stuff the whole thing in your pack. Highly recommended. Works great as sleeping sack if at a hostel ( reactor on top of bag ), or as a summer bag. Will always be part of my pack.
    Date published: 2014-03-16
    Rated4out of5byfromGood but not greatTook this liner up Kilimanjaro and used it 6 out of 7 nights. Lowest temperature was roughly 15 degrees we slept in at base camp. This liner definitely helped keep warm and I noticed a good difference when placing my arms outside of the liner. However, +25 degrees is a stretch. I would say 10-15 degrees is the best addition to a sleeping bag you'll get. It just seems too thin. However, it is very light, packs down very small, and pretty comfortable. If survival is an issue, you're likely going to get more warmth from a simple reflective emergency blanket that is 1/60 of the cost of this liner. It is hard to recommend this, but there is very little alternative to add warmth without adding layers or purchasing a warmer bag. Using a fleece liner is not an option when weight and packability is a must. I think there is a real gap in the warm bag liner market at the moment. This tries to fill that gap, but only does a satisfactory job.
    Date published: 2014-03-15
    Rated5out of5byfromMust have!Tried this extreme liner in my 15 degree B.A. Lost ranger bag on a trip to kinsman pond last weekend. Temps were around 18 with wind and blowing snow, roughly -20 or so with the wind chill, and this liner made my bag perfect to sleep in, I was actually so warm I had to unzip and air out the bag to keep from being too warm. The liner was very easy to pack in with the sleeping bag or leave it in its own bag
    Date published: 2014-02-07
    Rated4out of5byfromAdds WarmthUsed this with my old Squall North Face sleeping bag. When temps got down to 22 degrees, I was happy to have this liner around me. It didn't do much to insulate me from the cold ground but I don't think it is designed for insulation from ground freeze. Use this with a good sleeping bag along with a good ground pad and you'll be happy.
    Date published: 2013-11-12
    Rated4out of5byfromGets the job doneUsed it with a 20 degree bag in 19 degree weather. Slept comfortably through the night.
    Date published: 2013-10-09
    Rated5out of5byfromLight, comfortable and effectiveIt filled the need at temps between the comfort range of my summer bag and when I would turn to my winder bag. It didn't twist up inside my bag and was very comfortable to sleep in. It was also easier to clean than my down back would be.
    Date published: 2013-09-05
    Rated5out of5byfromGreat Product!!!Very light, very compact and fits well in it's included pack bag. This is with me at all times. Also keeps the dirt, sweat and oil out of the bag.
    Date published: 2013-09-04
    Rated1out of5byfromNopeI've looked at these bags at length with the idea of a stand alone bag, ultralight, with warm clothing as a booster for bike and ultralight hike trips. So I finally made the plunge with the knowledge that I had the pickup to sleep in if all went wrong. Sigh. I was out of the tent even before it was dark and into the truck cab for an awkward nights sleep. The bag could not keep me warm even in the truck. I don't need a booster for my down bag. It does a wonderful job keeping me warm but its 2 pounds and this product is something less than a pound. So my experiment is at fail. Get a light down bag and don't buy into this as a summer weight bag which is one of their claimed uses. Its not. I returned this to my local REI. The staff there was friendly and their return service was great.
    Date published: 2013-08-24

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