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Lightweight Base Layers

(118 products)
Products (118)
Remove underwear-weight filter:Lightweight
Sort: Best Match
    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $66.93 - $100.00
    101 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Women's
    $100.00
    134 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    SmartwoolClassic All-Season Merino T-Shirt - Women's
    $95.00
    98 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    SmartwoolClassic All-Season Merino T-Shirt - Men's
    $95.00
    98 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Arc'teryxRho LT Zip-Neck Base Layer Top - Men's
    $120.00
    109 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 - Men's
    $100.00
    28 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolClassic All-Season Merino Base Layer Bottoms - Women's
    $100.00
    24 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
    32 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Half-Zip Base Layer Top - Men's
    $44.83 - $67.39
    Save 25% - 50%
    compared to  $89.95
    124 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    HalfdaysSophia Base Layer Leggings - Women's
    $65.93 - $95.00
    123 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
  • Sale Ends Mar 23
    REI Co-opMerino 185 Base Layer Bottoms - Women's
    $59.89
    Save 25%
    compared to  $79.95
    121 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 Bottoms - Men's
    $44.95
    27 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    Kari TraaRose High-Waisted Base Layer Pants - Women's
    $64.83 - $120.00
    14 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
  • Sale Ends Mar 23
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Women's
    $59.89
    Save 25%
    compared to  $79.95
    239 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
  • Sale Ends Mar 23
    REI Co-opMerino 185 Base Layer Bottoms - Men's
    $59.89
    Save 25%
    compared to  $79.95
    162 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 Tights - Women's
    $44.95
    10 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus, Petite
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Men's
    $44.95
    36 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Women's
    $34.95
    23 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    tasc PerformanceElevation Merino Base Layer Bottoms - Men's
    $34.73 - $54.73
    Save 30% - 56%
    compared to  $79.00
    43 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    tasc PerformanceElevation Merino T-Shirt - Women's
    $54.73
    Save 30%
    compared to  $79.00
    93 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Plus, Regular
    REI OUTLET
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    Terms apply
    tasc PerformanceElevation Merino Base Layer Bottoms - Women's
    $54.73
    Save 30%
    compared to  $79.00
    66 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI OUTLET
    Arc'teryxRho Base Layer Bottoms - Women's
    $100.00
    37 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    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
    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
    REI Co-opLightweight Half-Zip Base Layer Top - Women's
    $49.95
    16 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    tasc PerformanceElevation Merino T-Shirt - Men's
    $34.73 - $54.73
    Save 30% - 56%
    compared to  $79.00
    52 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    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, Tall
    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
  • Sale Ends Mar 23
    Top Rated
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Men's
    $59.89
    Save 25%
    compared to  $79.95
    222 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMerino 185 Long-Sleeve Base Layer Top - Women's Plus Sizes
    $49.93
    Save 37%
    compared to  $79.95
    29 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Plus
1–30 of 118 products
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