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Men's Underwear

(156 products)
Products (156)
Sort: Best Match
    REI Co-opMerino Boxer Briefs - Men's
    $39.95
    114 reviews with an average rating of 4.2 out of 5 stars
    Size Type:
    Regular, Big
    REI Co-opHeavyweight Merino Long-Sleeve Base Layer Crew Top - Men's
    $49.83 - $99.95
    44 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Half-Zip Base Layer Top - Men's
    $44.83 - $89.95
    127 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opHeavyweight Merino Base Layer Bottoms - Men's
    $49.83 - $99.95
    20 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    REI Co-opEveryday Boxers - Men's
    $24.95
    135 reviews with an average rating of 4.2 out of 5 stars
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opMidweight Long-Sleeve Base Layer Top - Men's
    $26.83 - $54.95
    204 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    REI Co-opEveryday Boxer Briefs - Men's
    $24.95
    159 reviews with an average rating of 4.2 out of 5 stars
    Size Type:
    Regular, Big
    SaxxVolt Breathable Mesh Boxer Briefs - Men's
    $26.73
    Save 23%
    compared to  $35.00
    8 reviews with an average rating of 4.3 out of 5 stars
    Size Type:
    Regular, Big
    REI OUTLET
    SaxxQuest Quick-Dry Boxer Briefs - Men's
    $34.00
    0 reviews
    Size Type:
    Regular, Big
    REI Co-opMidweight Base Layer Bottoms - Men's
    $54.95
    101 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opMidweight Base Layer Half-Zip Top - Men's
    $29.83 - $59.95
    186 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    Royal RobbinsReadyDry Boxers - Men's
    $19.73
    Save 29%
    compared to  $28.00
    0 reviews
    Size Type:
    Regular, Big
    REI OUTLET
    REI Co-opMerino Boxers - Men's
    $39.95
    80 reviews with an average rating of 4.3 out of 5 stars
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Men's
    $68.83 - $125.00
    1537 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    tasc PerformanceElevation Merino Base Layer Bottoms - Men's
    $49.73 - $54.73
    Save 30% - 37%
    compared to  $79.00
    43 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    Top Rated
    PatagoniaCapilene Midweight Crew Base Layer Top - Men's
    $43.83 - $89.00
    91 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI Co-opMerino 185 Base Layer Bottoms - Men's
    $79.95
    164 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $53.83 - $100.00
    104 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    tasc PerformanceElevation Merino T-Shirt - Men's
    $34.73 - $54.73
    Save 30% - 56%
    compared to  $79.00
    53 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    SmartwoolMerino Print Boxer Briefs - Men's
    $34.73
    Save 27%
    compared to  $48.00
    8 reviews with an average rating of 3.1 out of 5 stars
    Size Type:
    Regular
    REI OUTLET
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    Earn 15% in total rewards

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    Terms apply
    PatagoniaCapilene Midweight Zip-Neck Base Layer Top - Men's
    $48.83 - $99.00
    75 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Men's
    $44.95
    27 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Men's
    $79.95
    223 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit 6" Boxer Briefs - Men's
    $36.73
    Save 26%
    compared to  $50.00
    7 reviews with an average rating of 3.1 out of 5 stars
    Size Type:
    Regular, Big
    REI OUTLET
    New arrival
    SmartwoolMerino Boxer Briefs - Boxed - Men's
    $50.00
    0 reviews
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic Thermal Merino Quarter-Zip Base Layer Top - Men's
    $71.83 - $130.00
    56 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SaxxQuest Quick-Dry Boxer Briefs - Men's - Package of 2
    $61.00
    0 reviews
    Size Type:
    Regular, Big
    REI Co-opHeavyweight Merino Base Layer Half-Zip Top - Men's
    $49.83 - $104.95
    27 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    REI Co-opMerino 185 Base Layer Top - Men's
    $69.95
    59 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Men's
    $44.95
    38 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
1–30 of 156 products
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