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Base Layers

(302 products)
Products (302)
Sort: Best Match
    REI Co-opHeavyweight Merino Base Layer Half-Zip Top - Men's
    $49.83 - $104.95
    31 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Women's
    $44.95
    37 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opMidweight Long-Sleeve Base Layer Top - Men's
    $26.83 - $54.95
    211 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
    $71.83 - $130.00
    71 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Top Rated
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Men's
    $125.00
    646 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
    $71.83 - $130.00
    61 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
    $68.83 - $125.00
    1539 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opMidweight Base Layer Bottoms - Men's
    $54.95
    104 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Women's
    $53.83 - $100.00
    92 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI Co-opMidweight Base Layer Tights - Women's
    $54.95
    126 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus, Petite
    REI Co-opHeavyweight Merino Long-Sleeve Base Layer Crew Top - Men's
    $49.83 - $99.95
    49 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $68.83 - $125.00
    1221 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    REI Co-opMidweight Long-Sleeve Base Layer Top - Women's
    $54.95
    324 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    REI Co-opHeavyweight Merino Base Layer Bottoms - Women's
    $49.83 - $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-opMerino 185 Long-Sleeve Half-Zip Base Layer Top - Men's
    $44.83 - $89.95
    133 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
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    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $53.83 - $100.00
    106 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $84.73
    Save 26%
    compared to  $115.00
    279 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    REI Co-opMerino 185 Base Layer Bottoms - Men's
    $79.95
    167 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Men's
    $44.95
    28 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opMidweight Base Layer Bottoms - Kids'
    $25.93
    Save 25%
    compared to  $34.95
    14 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
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    tasc PerformanceElevation Merino T-Shirt - Men's
    $46.73 - $54.73
    Save 30% - 40%
    compared to  $79.00
    55 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Men's
    $44.95
    41 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opHeavyweight Merino Base Layer Half-Zip Top - Women's
    $51.83 - $104.95
    35 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Women's Plus Sizes
    $39.83
    Save 50%
    compared to  $79.95
    35 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Plus
    Top Rated
    SmartwoolClassic All-Season Merino Quarter-Zip Base Layer Top - Women's
    $69.73
    Save 26%
    compared to  $95.00
    6 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Men's
    $84.73
    Save 26%
    compared to  $115.00
    318 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI OUTLET
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $125.00
    768 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Men's
    $79.95
    228 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    Arc'teryxRho Base Layer Hoody - Women's
    $95.73
    Save 20%
    compared to  $120.00
    25 reviews with an average rating of 4.9 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    Top Rated
    REI Co-opMidweight Base Layer Half-Zip Top - Men's
    $29.83 - $59.95
    193 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
1–30 of 302 products
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