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Sea to Summit Reactor Plus Thermolite Compact Liner

Combining 2 different weight fabrics, this Sea to Summit Reactor Plus Themolite® mummy bag liner adds a few degrees of warmth and extends the life of your sleeping bag.
  • $59.95

Item # 797113

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  • Constructed of insulating Thermolite fabric, a hollow-core, breathable fiber that provides extraordinary warmth for its weight
  • Combined with the regular 80g/m² Thermolite, super insulating 110g/m² Thermolite panels provide added warmth in the torso and foot bed areas
  • Adds up to 20°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
  • Sea to Summit Reactor Plus Themolite comes with a lightweight Ultra-Sil™ stuff sack
  • Compact, short design is ideal for women or anyone under 6 ft. tall

Sea to Summit Reactor Plus Thermolite Compact Liner

Specification Description
Best use Backpacking
Sleeping bag shape Mummy
Added warmth (F) Up to 20 degrees
Added warmth (C) Up to 11.1 degrees
Stuff sack size 4 x 6 inches
Material(s) Polyester
Dimensions 72 x 36 inches
Weight 9.3 ounces
Weight - metric 0.26 kilograms
Trademarked terms Thermolite

Sea to Summit Reactor Plus Thermolite Compact Liner

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Rated 4.1429/5 based on 7 reviews
Rated 3out of5
by fromDid not stay put at night My 12 year-old son took it on a camping trip with his scout troop. He said it ended up at his feet by the next morning so it didn't help much; he's an active sleeper. It's too bad because we love how compact it is.
Date published: 2011-12-07
Rated 4out of5
by fromWorks better than expected! I got the Reactor Plus liner to add some versatility to my current sleep system. I have the REI Downtime 20 degree down bag, as well as a closed cell foam pad and a 3/4 length inflatable foam core pad. When I first got the liner, I was skeptical about the 20 degrees F warmer claim. The material is very thin. The liner is also very short. I am 5'11" on a good day and the hood will BARELY cinch over my face. I normally just cinch it under my chin. The first time I used the liner I was hammocking in below freezing temps and I could certainly tell the difference when my shoulder was inside the bag or outside the bag. The second use was the real test. During a blizzard I pitched my tent and slept the night out behind my apt. The temps dipped to 5 degrees and the windchill was at least -20. I was toasty warm all night. I am certain that it could have been 10 degrees colder and I would have remained warm. The liner also does a great job of keeping the bag dry from perspiration. The material absorbs moisture and keeps the bag from getting clammy. Overall I am very excited with this liner and I hope to use it in some even colder temps to come.
Date published: 2010-12-19
Rated 3out of5
by fromComfy but not as warm as advertised Very comfortable. Will use to add a little warmth and to keep sleeping bag clean. Packs down very nicely in provided bag and can tuck anywhere in pack. Disappointed that it was advertised as adding up to 20 degrees(F) of warmth. That would be a miracle. I'd estimate maybe 5 degrees. Marked down my rating for that reason.
Date published: 2013-05-19
Rated 4out of5
by fromNot to shabby I bought the liner to add a little extra warmth to my old sleeping bag for a winter camping trip. The bag only had a 25degree rating, so i was hoping to squeeze a little more out of it with this. It definitely added extra warmth, but the 20degrees extra is a bit of a stretch. The temp was about 25 over night and i was cold, but just cold enough to be uncomfortable. So for my last trip I bought the radiant down sleeping bag which has a 20 degree rating, so I used the liner with that bag. The temp got down to about 10 degrees, it worked well i was warm all night even without an insulated sleeping pad. To sum it all up, if your hoping to squeeze a little more out of your bag on a trip that will be colder that your bag is rated for this would work but don't expect 20 more degrees out of it.
Date published: 2013-02-18
Rated 5out of5
by fromCozy Sleeping Bag Liner Liner gives just the litle bit of warmth needed to sleep comfortably all night. Definitely glad I bought it.
Date published: 2013-06-26
Rated 5out of5
by fromComfy, stretchy, multi-purpose Bought this to use as a blanket on bus trips through rural Costa Rica, and to sleep in on hot nights. Perfect for both!
Date published: 2014-07-07
Rated 5out of5
by fromPerfect. Lightweight, inexpensive, warm. Used during a 3-day AT hike through Maryland in early December. Perfect way to add another layer of warmth without purchasing an entirely new sleeping bag rated for colder weather. Added a surprising amount of warm given that it's so thin. The liner is considerably less expensive than another sleeping bag, is incredibly lightweight, and very comfortable. I did not feel any "bunching" or "wrapping" while in my sleeping bag (the liner moved and rotated with my body. Completely worthwhile investment. If you're a cold-natured person, consider the same liner that "adds more warmth"; hot-natured people, consider the lighter version.
Date published: 2013-01-02

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