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Base Layers

(311 products)
Products (311)
Sort: Best Match
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Women's
    $49.83 - $100.00
    105 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Women's
    $44.95
    44 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opMidweight Long-Sleeve Base Layer Top - Men's
    $19.83 - $54.95
    214 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    SmartwoolClassic Thermal Merino Quarter-Zip Base Layer Top - Women's
    $49.83 - $130.00
    75 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Plus, Regular
    Top Rated
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Men's
    $125.00
    650 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic Thermal Merino Quarter-Zip Base Layer Top - Men's
    $130.00
    64 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Men's
    $125.00
    1544 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Half-Zip Base Layer Top - Men's
    $89.95
    140 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $59.83 - $125.00
    1226 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $100.00
    108 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMidweight Long-Sleeve Base Layer Top - Women's
    $54.95
    327 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    SmartwoolClassic All-Season Merino Base Layer Bottoms - Women's
    $49.83 - $100.00
    25 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI Co-opMidweight Base Layer Tights - Women's
    $54.95
    127 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus, Petite
    Top Rated
    REI Co-opMidweight Base Layer Half-Zip Top - Men's
    $59.95
    195 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opMidweight Base Layer Bottoms - Men's
    $54.95
    105 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opLightweight Base Layer Tights - Women's
    $44.95
    11 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus, Petite
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Men's
    $44.95
    29 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Men's
    $44.95
    43 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Women's
    $79.95
    246 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Men's
    $79.95
    230 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
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    REI Co-opHeavyweight Merino Base Layer Bottoms - Women's
    $29.83 - $99.95
    34 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opHeavyweight Merino Long-Sleeve Base Layer Crew Top - Men's
    $99.95
    50 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $125.00
    771 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI Co-opMerino 185 Base Layer Bottoms - Men's
    $79.95
    169 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMidweight Base Layer Half-Zip Top - Women's
    $59.95
    201 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Top Rated
    IcebreakerMerino 200 Oasis Long-Sleeve Crewe Thermal Top - Women's
    $120.00
    189 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Top Rated
    Arc'teryxRho LT Crew Neck Base Layer Top - Men's
    $75.93 - $100.00
    46 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    tasc PerformanceElevation Merino Base Layer Bottoms - Men's
    $46.73 - $54.73
    Save 30% - 40%
    compared to  $79.00
    44 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    SmartwoolClassic All-Season Merino Base Layer Bottoms - Men's
    $100.00
    30 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMerino 185 Base Layer Bottoms - Women's
    $79.95
    124 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
1–30 of 311 products
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