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Underwear

(550 products)
Products (550)
Sort: Best Match
    REI Co-opMerino Bikini Underwear - Women's
    $27.95
    65 reviews with an average rating of 4.1 out of 5 stars
    Size Type:
    Regular, Plus
    REI Co-opMerino Boxer Briefs - Men's
    $39.95
    126 reviews with an average rating of 4.2 out of 5 stars
    Size Type:
    Regular, Big
    REI Co-opMerino Bralette
    $44.95
    Top Rated
    216 reviews with an average rating of 4.6 out of 5 stars
    Bra Support:
    Low Impact
    Support Style:
    Encapsulation
    Fabric:
    48% merino wool/32% TENCEL lyocell/15% nylon/5% LYCRA spandex
    REI Co-opMerino 185 Long-Sleeve Crew Base Layer Top - Men's
    $84.95
    Top Rated
    5 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    REI Co-opEveryday Boxers - Men's
    $24.95
    153 reviews with an average rating of 4.2 out of 5 stars
    Size Type:
    Regular, Big
    REI Co-opEveryday Boxer Briefs - Men's
    $24.95
    170 reviews with an average rating of 4.1 out of 5 stars
    Size Type:
    Regular, Big
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $125.00
    Top Rated
    1541 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Boody Eco WearFull Briefs - Women's - Package of 2
    $26.73
    Save 21%
    compared to  $33.95
    REI Outlet
    5 reviews with an average rating of 4.4 out of 5 stars
    Size Type:
    Regular
    REI Co-opMerino Hipster Underwear - Women's
    $29.95
    61 reviews with an average rating of 3.9 out of 5 stars
    Size Type:
    Regular, Plus
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Men's
    $125.00
    Top Rated
    1115 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $84.73 - $86.97
    Save 26% - 30%
    compared to  $115.00 - $125.00
    REI Outlet
    289 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic Thermal Merino Base Layer Quarter-Zip - Women's
    $89.97
    Save 30%
    compared to  $130.00
    REI Outlet
    Top Rated
    1100 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI Co-opMerino 185 Base Layer Bottoms - Men's
    $84.95
    Top Rated
    5 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $125.00
    Top Rated
    1089 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    SaxxQuest Quick-Dry Boxer Briefs - Men's
    $36.00
    Top Rated
    62 reviews with an average rating of 4.7 out of 5 stars
    Size Type:
    Regular, Big
    REI Co-opActive Briefs - Women's
    $19.95
    45 reviews with an average rating of 4.1 out of 5 stars
    Size Type:
    Regular, Plus
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    REI Co-opMerino 250 Long-Sleeve Crew Base Layer Top - Men's
    $104.95
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    SaxxQuest Quick-Dry Boxer Briefs - Men's
    $97.00
    Top Rated
    23 reviews with an average rating of 4.7 out of 5 stars
    Size Type:
    Regular, Big
    SmartwoolIntraknit Merino 3/4 Base Layer Bottoms - Women's
    $83.87
    Save 30%
    compared to  $120.00
    REI Outlet
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Men's
    $125.00
    Top Rated
    764 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolClassic All-Season Merino Base Layer Long-Sleeve Shirt - Women's
    $69.97
    Save 30%
    compared to  $100.00
    REI Outlet
    Top Rated
    434 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    REI Co-opActive Bikini Underwear - Women's
    $19.95
    62 reviews with an average rating of 3.4 out of 5 stars
    Size Type:
    Regular, Plus
    REI Co-opMidweight Base Layer Bottoms - Men's
    $64.95
    Top Rated
    6 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    REI Co-opMidweight Base Layer Crew Top - Kids'
    $34.95
    Top Rated
    9 reviews with an average rating of 4.9 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $79.97 - $86.97
    Save 30%
    compared to  $115.00 - $125.00
    REI Outlet
    Top Rated
    1558 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic Thermal Merino Base Layer Quarter-Zip - Men's
    $89.73
    Save 25%
    compared to  $120.00
    REI Outlet
    Top Rated
    71 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI Co-opMerino 250 Base Layer Bottoms - Men's
    $104.95
    0 reviews
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    SmartwoolIntraknit Thermal Merino Base Layer 3/4 Bottoms - Men's
    $89.73
    Save 25%
    compared to  $120.00
    REI Outlet
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolClassic All-Season Merino T-Shirt - Men's
    $39.83 - $95.00
    486 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMidweight Long-Sleeve Crew Base Layer Top - Women's
    $64.95
    7 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
Sort: Best Match

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