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Base Layers

(338 products)
Products (338)
Sort: Best Match
    REI Co-opMidweight Base Layer Bottoms - Men's
    $54.95
    101 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $125.00
    1213 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opMidweight Long-Sleeve Base Layer Top - Men's
    $37.93 - $54.95
    197 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
    $130.00
    56 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Top Rated
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Men's
    $125.00
    639 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
    $130.00
    51 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
    $125.00
    1512 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $125.00
    761 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI Co-opHeavyweight Merino Long-Sleeve Base Layer Crew Top - Men's
    $69.93 - $99.95
    40 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    REI Co-opHeavyweight Merino Base Layer Bottoms - Women's
    $69.93 - $99.95
    33 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Plus
    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $66.93 - $100.00
    87 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMidweight Long-Sleeve Base Layer Top - Women's
    $54.95
    319 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    REI Co-opMidweight Base Layer Tights - Women's
    $54.95
    123 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus, Petite
    Top Rated
    REI Co-opHeavyweight Merino Base Layer Bottoms - Men's
    $69.93 - $99.95
    18 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    REI Co-opMidweight Base Layer Half-Zip Top - Men's
    $41.93 - $59.95
    181 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Women's
    $100.00
    140 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI Co-opHeavyweight Merino Long-Sleeve Base Layer Crew Top - Women's
    $69.93 - $99.95
    44 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Plus
    SmartwoolClassic All-Season Merino T-Shirt - Women's
    $95.00
    95 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opHeavyweight Merino Base Layer Half-Zip Top - Women's
    $72.93 - $104.95
    29 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Plus
    SmartwoolClassic All-Season Merino T-Shirt - Men's
    $95.00
    92 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
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    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
    SmartwoolClassic All-Season Merino Base Layer Bottoms - Women's
    $100.00
    23 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI Co-opMerino 185 Base Layer Bottoms - Men's
    $55.93 - $79.95
    161 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    PatagoniaCapilene Midweight Crew Base Layer Top - Men's
    $61.93 - $89.00
    89 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    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
    tasc PerformanceElevation Merino Base Layer Bottoms - Men's
    $34.73 - $54.73
    Save 30% - 56%
    compared to  $79.00
    42 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    Top Rated
    SmartwoolClassic Thermal Merino 3/4 Base Layer Bottoms - Men's
    $115.00
    85 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    tasc PerformanceElevation Merino T-Shirt - Women's
    $54.73
    Save 30%
    compared to  $79.00
    91 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI OUTLET
    Top Rated
    IcebreakerMerino 200 Oasis Long-Sleeve Crewe Thermal Top - Men's
    $69.93 - $120.00
    220 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI Co-opMidweight Base Layer Half-Zip Top - Women's
    $59.95
    192 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
1–30 of 338 products
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