• Online:
  • URL for this product:
  • From the U.S. and CanadaCall 1-800-426-4840
  • Mon. through Sun., 4 a.m. through 11 p.m. PT.
  • InternationalCall 1-253-891-2500
  • Mon. through Sun., 4 a.m. through 11 p.m. PT. English language only.
Sea to Summit CoolMax Adaptor Liner - Mummy

    Sea to Summit CoolMax Adaptor Liner - Mummy

    This Sea to Summit CoolMax® Adapter mummy bag liner is specifically designed for use in warm or humid conditions. Its moisture management fabric adapts to a variety of temperatures and humidity.

    • $47.95

    Item # 797111

    REI Members get back an estimated $ 4.80 on this item as part of their annual member refund.

    The REI Member Dividend

    The REI dividend is a unique benefit of membership in the REI co-op. It's comprised of your member refund—typically 10% back on eligible purchases—and/or your REI Visa® card rebates.

    Each March, active REI members and REI Visa cardholders who earned a rebate receive a refund in the form of an annual dividend notice.

    Only active members receive annual dividend notices. To maintain your active status as an REI member, you need to make net merchandise or shipping purchases of at least $10 per year, unless you joined that year. Member numbers are issued in one name and only that person receives the member refund. Your number can be used by others in your family, but it cannot be transferred to someone else.

    Questions? Call us at 1-800-426-4840 for more about your dividend or its redemption.

    Learn more

    Product size and color
    • 100% Satisfaction Guaranteed
    • Gear and Advice You Can Trust

    Orders of $50 or more ship for free.
    Learn more

    To view videos or use the zoom feature on REI's websites, please download the latest version of Adobe Flash Player.

    • CoolMax® polyester provides moisture-wicking, quick-drying comfort and offers the lightweight, softness of cotton
    • Use it as a part of your sleep system or by itself as a warm weather 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
    • The Sea to Summit CoolMax® Adapter liner comes with a lightweight Ultra-Sil™ stuff sack


    Item 797111

    REI Membership

    Sea to Summit CoolMax Adaptor Liner - Mummy Specs
    Best use
    3 x 5 inches
    CoolMax polyester
    82 x (shoulder) 36 x (foot) 12 inches
    8.6 ounces
    0.24 kilograms
    Sleeping bag shape
    Added warmth (F)
    Added warmth (C)
    Stuff sack size
    Weight - metric

    Sea to Summit CoolMax Adaptor Liner - Mummy

    Loading Ratings & Reviews...

    Rated 3.8333/5 based on 6 reviews
    Rated 3out of5
    by fromOk products, but could be better It's OK products, for minimalist campaign style. If you comfort driven you should choose cotton / silk blend liner. More space and more comfortable. CollMax synthetic feel sticky (could be my specific opinion). Also this product is seriously overpriced!
    Date published: 2013-09-04
    Rated 4out of5
    by fromSleeping bag liner I bought this for a cruise and hotel stays. Sometimes when your driving across country and you are ready to stop some place on your route, you will find all the nice hotels are full. If you have to stay in a "by the hour hotel" or 1 star hotel this sleeping bag liner will come in handy.
    Date published: 2014-02-20
    Rated 5out of5
    by fromSummer shell or winter liner -- cool! The prospect of stuffing my bag in a triple-loader is daunting, so the idea of a sheet to protect my comforter from sleep sweat was more than appealing. i took a look at a few different liners, & this one's worked out well, keeping me cool in summer heat & keeping my bag from getting stinky! It's a snap to wash and dries so quickly I barely knew it was wet! It's not constricting, stretches quite well, & you can even sew up the opening with the eskimo cord if you need to feel snug as a bug! The stuffsack is compact & fits in just about any little crevice in your pack or duffel. Great deal!
    Date published: 2011-06-13
    Rated 1out of5
    by fromNot worth the money Certainly not what I expected. The liner could benefit from a zipper, getting in it isn't easy...especially if you're a bigger or taller person. The material is thin and feels cheap. Personally feel it's about $30 overpriced for what you get, not worth the money and found it to be more of a hindrance. Will be returning the two I bought from REI.
    Date published: 2013-01-28
    Rated 5out of5
    by fromPerfect for sticky summer nights! This liner worked great as a lightweight summer shell when it was too hot for a sleeping bag of any kind but I didn't want to sleep in just my clothes. Used inside a sleeping bag on cooler nights it kept me from getting sticky and sweaty - I'd usually wake up toasty warm, sometimes TOO warm, but never sticky with sweat, which was really nice. I think it definitely adds a little bit of insulation on colder nights - I am a cold sleeper and I normally use a 15 or 20˚ down bag and tend to get chilly without extra clothes on when it is cooler than about 40˚, but we unexpectedly encountered temps into the 30's on our last camping trip and I never once woke up cold using this liner. It also packs down to about the size of a softball so there's no reason not to bring it along. It's also more easily washable than your sleeping bag (and it even dries quickly when hand washed) and it's really nice to slip into something "clean" to sleep in after a long day of hiking when you don't have access to real laundry facilities.
    Date published: 2012-12-29
    Rated 5out of5
    by fromGreat for long camping trips I work as a conservation biologist and spend months camping in the backcountry. I bought this about a year ago for a new position camping in high elevation rainforest. Conditions range from frigid to swampy and this product stays dry and comfortable through it all. I bought this originally to save wear-and-tear on company sleeping bags as well as providing another, thin layer for warm evenings. I have to say, after a solid year of use, it looks new and I still love it. I struggle with mildewy smells and damp fabrics from every outdoor gear/clothing I take (including top-of-the line brands) EXCEPT for this liner. I can't express how nice it is to slip into a cool, DRY liner after a day in the cold rain. I will also add that I am not one to write reviews let alone 5-star reviews. This one is worth it.
    Date published: 2013-11-11

    Ask a question and have it answered by REI product experts and fellow outdoor enthusiasts. Need immediate assistance? Use Live Help.

    Loading Questions & Answers...

    How are we doing? Give us feedback on this page.

        FREE SHIPPING With $50 minimum purchase

        • Join REI today!
        • REI Membership
        • REI member benefits include an annual refund (typically 10% on eligible purchases).
        • Join REI today!
        • Sign up for REI Gearmail®
        • and get 15% off selected items!
        • Store Locator
        • Locate an REI store near you.
        • Find a Store
        © 2014 Recreational Equipment, Inc. All rights reserved. REI, the REI Tree and Mountain design, Novara, and
        REI Adventures are trademarks of Recreational Equipment, Inc.

        Find REI on: FacebookTwitterYouTubeFlickrMobile site