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Lightweight Base Layers

(106 products)
Products (106)
Remove underwear-weight filter:Lightweight
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    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
    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-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
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Women's
    $44.95
    43 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $100.00
    109 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    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
    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-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
    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
    SmartwoolClassic All-Season Merino Quarter-Zip Base Layer Top - Women's
    $69.73
    Save 26%
    compared to  $95.00
    7 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    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
    REI Co-opMerino 185 Base Layer Bottoms - Women's
    $79.95
    123 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    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
    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
    SmartwoolClassic All-Season Merino T-Shirt - Women's
    $95.00
    111 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opLightweight Half-Zip Base Layer Top - Women's
    $49.95
    18 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Men's
    $34.95
    37 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    SmartwoolClassic All-Season Merino T-Shirt - Men's
    $95.00
    118 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMerino 185 Base Layer Top - Women's
    $69.95
    68 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Women's
    $34.95
    31 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
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    Terms apply
    tasc PerformanceElevation Merino T-Shirt - Women's
    $46.73 - $54.73
    Save 30% - 40%
    compared to  $79.00
    95 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI OUTLET
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Half-Zip Base Layer Top - Women's
    $89.95
    113 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI Co-opLightweight Half-Zip Base Layer Top - Men's
    $49.95
    24 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit Thermal Merino Colorblock Crew Base Layer Top - Men's
    $130.00
    13 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    tasc PerformanceElevation Merino Base Layer Bottoms - Women's
    $46.73 - $54.73
    Save 30% - 40%
    compared to  $79.00
    67 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI OUTLET
    Top Rated
    Arc'teryxSatoro Merino Wool Crew Neck Long-Sleeve Base Layer Top - Women's
    $95.73
    Save 20%
    compared to  $120.00
    18 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI OUTLET
    Kari TraaKlara High-Waisted Base Layer Pants - Women's
    $62.73 - $66.73
    Save 25% - 30%
    compared to  $90.00
    14 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    tasc PerformanceElevation Merino T-Shirt - Men's
    $46.73 - $54.73
    Save 30% - 40%
    compared to  $79.00
    56 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    REI Co-opMerino 185 Base Layer Top - Men's
    $69.95
    61 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Arc'teryxRho LT Base Layer Bottoms - Men's
    $59.83 - $100.00
    61 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
1–30 of 106 products
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