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Lightweight Base Layers

(119 products)
Products (119)
Remove underwear-weight filter:Lightweight
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    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $66.93 - $100.00
    85 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 - Men's
    $79.95
    161 reviews with an average rating of 4.2 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
    220 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Men's
    $44.95
    26 reviews with an average rating of 4.5 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
    33 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    Arc'teryxRho LT Crew Neck Base Layer Top - Men's
    $100.00
    40 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    Arc'teryxRho LT Zip-Neck Base Layer Top - Men's
    $120.00
    105 reviews with an average rating of 4.5 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
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    51 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    tasc PerformanceElevation Merino Base Layer Bottoms - Men's
    $34.73 - $54.73
    Save 30% - 56%
    compared to  $79.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    41 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Half-Zip Base Layer Top - Men's
    $62.93 - $89.95
    121 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Arc'teryxRho LT Base Layer Bottoms - Men's
    $100.00
    59 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolClassic All-Season Merino Base Layer Bottoms - Men's
    $100.00
    27 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    Arc'teryxRho LT Base Layer Hoody - Men's
    $120.00
    57 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Free CountryCloud Knit Crewneck Base Layer Top - Men's
    $26.73
    Save 33%
    compared to  $40.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    9 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    REI Co-opMerino 185 Base Layer Bottoms - Women's
    $79.95
    119 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Arc'teryxRho Base Layer Bottoms - Women's
    $24.83 - $100.00
    37 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Women's
    $79.95
    238 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    SmartwoolClassic All-Season Merino 3/4 Base Layer Bottoms - Men's
    $85.00
    4 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 - Men's
    $95.00
    96 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit Thermal Merino Base Layer Bottoms - Men's
    $150.00
    32 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
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    Terms apply
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Men's
    $14.83 - $34.95
    26 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    Free CountryForce Grid Fleece Base Layer Top - Men's
    $29.73
    Save 33%
    compared to  $45.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    17 reviews with an average rating of 4.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big
    REI OUTLET
    Free CountryForce Grid Fleece Base Layer Bottoms - Men's
    $29.73
    Save 33%
    compared to  $45.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    19 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Women's
    $44.95
    31 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    tasc PerformanceElevation Merino T-Shirt - Women's
    $54.73
    Save 30%
    compared to  $79.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    91 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI OUTLET
    Free CountryCloud Knit Base Layer Bottoms - Men's
    $26.73
    Save 33%
    compared to  $40.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    3 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    REI Co-opMerino 185 Base Layer Top - Men's
    $69.95
    58 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Women's
    $100.00
    133 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opLightweight Half-Zip Base Layer Top - Men's
    $49.95
    19 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Kari TraaKlara High-Waisted Base Layer Pants - Women's
    $62.73 - $66.73
    Save 25% - 30%
    compared to  $90.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    13 reviews with an average rating of 3.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
1–30 of 119 products
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