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Cocoon CoolMax Mummy Liner


    Cocoon CoolMax Mummy Liner

    Add comfort to your mummy bag with this breathable, moisture-wicking CoolMax® liner.

    • $44.95

    Item # 649745

    REI Members get back an estimated $ 4.50 on this item as part of their annual member refund.

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    • Keeps your bag clean, saving it from the wear and tear inflicted by washing machines
    • Adds 8.4 degrees of warmth to your sleeping bag
    • Width tapers from 32" at the shoulder to 24" at the foot
    • Comes with stuff sack for convenient packing


    Item 649745

    REI Membership

    Cocoon CoolMax Mummy Liner Specs
    Best use
    Up to 5 degrees
    Up to 2.8 degrees
    3.5 x 7 inches
    CoolMax polyester
    86 x 32(shoulder) x 24(at foot) inches
    9 ounces
    0.26 kilograms
    Sleeping bag shape
    Added warmth (F)
    Added warmth (C)
    Stuff sack size
    Weight - metric

    Cocoon CoolMax Mummy Liner

    Loading Ratings & Reviews...

    Rated 4.3333/5 based on 21 reviews
    Rated 3out of5
    by fromGlad I bought this Bought this in preparation for a cross country cycling trip next summer. I had a chance to break it in during RAGBRAI (Iowa) last month. On hot nights it was a perfect lightweight blanket - I did not even get in it. On cooler nights it was great by it self as a bag (though not always easy to get out of during the night.) I did not take my sleeping bag, so on cool nights I used the liner while wearing long sweat pants and wool long sleeved shirt. No problems down to 60 degrees.
    Date published: 2013-08-07
    Rated 4out of5
    by fromConvenient I found this liner to be a great summer bag for early night time, offering a little coverage without making me sweat. It also turned out to double as a superb mosquito netting, though I suppose you could find a lighter net. I was happy with it in my average-weight pack, but I may rethink when I go UL.
    Date published: 2008-07-26
    Rated 4out of5
    by fromIt actually does work! I bought this liner on a whim to keep my bags (and my little son's) clean. It turns out that this thin little "baggy" actually does add a bit of heat retention. I was pleasantly surprised that it actually kept me warmer than I'd thought, even though I still plan to buy a warmer liner so I don't need to buy a more expensive bag. I'm a bit confused why the call it CoolMax... I expected it'd only be good to keep the bag clean and absorb sweat when it's hot, but it actually does more. Unfortunately, I didn't have it along when I really needed it on the PCT during a storm at 32.5 degrees, so I can't comment on how it performs when wet (EVERYTHING was wet, even the tent was raining on the inside). The material appears pretty thin and sensitive, and I imagine it'd be pretty easy to rip it, but I'm pretty careful and haven't had an issue yet. Some folks complain that the only way in is from the top, so here's what I do: I carefully put the liner on like a pair of pants (but up under my shoulders), then I slip into my bag like everyone else, and then sit up and adjust the liner and then the bag. No problems for me.
    Date published: 2010-02-28
    Rated 4out of5
    by fromperfect for hiking the High Sierras It was a little colder than we anticipated in the higher altitudes---the sack was warm enough, but we would have liked something a little more substantial-----we were not cold, so it was fine.
    Date published: 2007-09-04
    Rated 4out of5
    by fromSurprising effective... The product was thinner and lighter than I had initially expected but it was very effective in upgrading the warmth of my mummy bag. In the past I had needed to rely on wearing fleece underwear and piling on jackets or sweaters on top of my bag to keep warm at night.
    Date published: 2014-08-25
    Rated 4out of5
    by fromClean bag, comfy sleep I regularly use sleeping bag liners, primarily to help keep my bags clean. This liner is very comfortable, stretching and comforming easily if tossing and turning is the order of the night. Have also used it by itself on warm summer nights. I would like to see an option for some kind of side opening. Climbing in or out from the top can be a little awkward.
    Date published: 2007-09-24
    Rated 5out of5
    by fromKeeps the bag clean, adds warmth Bought two of these before we went on a month long road trip with 2/3 of the nights sleeping in this liner and a sleeping bag. The liner is very soft and comfortable and helped keep the bags clean! It's much easier to just toss the liner in the wash than the bag itself, so we could launder them in the middle of the long trip if they became stinky.
    Date published: 2013-10-24
    Rated 5out of5
    by fromGreat, light bag As a soldier, space is very limited when i deploy. This bag is great by itself in slightly cool places and wonderful as a bag liner. It may look thin, but it works great.
    Date published: 2007-10-04

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