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Lightweight Base Layers

(108 products)
Products (108)
Remove underwear-weight filter:Lightweight
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    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Women's
    $49.83 - $100.00
    100 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $39.83 - $100.00
    106 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 Half-Zip Base Layer Top - Men's
    $89.95
    137 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    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
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Women's
    $44.95
    38 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, 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
    SmartwoolClassic All-Season Merino T-Shirt - Women's
    $95.00
    110 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    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
    SmartwoolIntraknit Thermal Merino Colorblock Crew Base Layer Top - Men's
    $49.83 - $130.00
    12 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-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
    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
    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 Crew Base Layer Top - Women's
    $34.95
    30 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    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
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    REI Co-opMerino 185 Base Layer Top - Men's
    $69.95
    60 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Top Rated
    REI Co-opLightweight Half-Zip Base Layer Top - Women's
    $49.95
    17 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    Arc'teryxRho LT Zip-Neck Base Layer Top - Men's
    $84.83 - $120.00
    111 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
    122 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    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
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    Icebreaker125 Cool-Lite Merino Blend Sphere III Scoop T-Shirt - Women's
    $90.00
    28 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    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:
    Plus, Regular
    REI OUTLET
    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
    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 Top - Women's
    $69.95
    67 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Arc'teryxRho Base Layer Bottoms - Women's
    $59.83 - $100.00
    38 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    Icebreaker200 Oasis Long-Sleeve Half-Zip Base Layer Top - Women's
    $56.83 - $130.00
    42 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    SmartwoolClassic All-Season Merino T-Shirt - Men's
    $95.00
    111 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Men's
    $34.95
    32 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    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
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