REI Co-op Merino Thong Underwear - Women's

Color: Sea Forest
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Members get an estimated $2.50 back on this item as a part of your annual .

Members get an estimated $2.50 back on this item.
To buy,  sign in as an REI Co-op Member or join now.

Avoid panty lines on the trail in the soft, breathable and naturally odor-resistant REI Co-op Merino Merino Thong Underwear for women. They're made to keep you comfy throughout the day.

  • Features

    • Ultrafine 150 g core-spun nylon, wrapped in merino, offers a soft feel without any itchiness
    • Certified merino wool naturally breathes, wicks away sweat, dries quickly and resists odors, making it an ideal multiday trip companion
    • Flat seams and merrow stitch construction eliminate chafing
    • Soft elastic trim keeps underwear in place
    • Designed to hug the body for optimum performance
    • Machine washable
    • Made in a Fair Trade Certified™ factory, which promotes safe working conditions and sustainable livelihoods
    • Made using wool certified to the Responsible Wool Standard (RWS), which requires that sheep are treated in accordance with leading animal welfare standards
    • Pairs with Merino Bralette and Merino Base Layer Tank Top (not included)


    View all REI Co-op Women's Briefs
  • Technical Specs

    Best Use


    Underwear Style



    48% merino/32% TENCEL lyocell/15% nylon/5% LYCRA spandex

    Moisture Wicking


    Quick Drying





    Fair Trade Certified™ factory

    Wool certified to the Responsible Wool Standard (RWS)

  • Size Chart

    Numerical Size000-24-68-1012-14161820-2224-2602468101214161820222426
    Sleeve Length29.53030.53131.532.533.533.534.5303030.530.5313131.531.532.533.533.533.534.534.5

    Sizing Notes

    Measurements are stated in inches unless otherwise indicated. Some women's pants are available in petite and tall sizes. Typically petite sizes fit women 4'11" to 5'3". Regular sizes fit women 5'4" to 5'8". Tall sizes fit women 5'9" to 5'11".

    PETITE: Generally, as compared to regular sizes, petite sizes are 2.5 inches shorter in inseam, 1 inch shorter in body length, 1.25 inches shorter in sleeve length and ¾ inch shorter in total rise.

    TALL: tall sizes are 3 inches longer in inseam, 2 inches longer in body length, 2.5 inches longer in sleeve length and 1.25 inches longer in total rise.

    Capri or cropped pants have an intentionally shorter inseam—reference the technical specs instead of this chart.

  • Reviews
    18 reviews with an average rating of 3.9 out of 5 stars

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