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Smartwool Long Sleeve Base Layers

(35 products)
Products (35)
Remove brand filter:SmartwoolRemove sleeve-length filter:Long SleeveClear all
Sort: Best Match
    Top Rated
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Men's
    $66.93 - $100.00
    99 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    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
    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
    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
    SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Men's
    $92.73
    Save 28%
    compared to  $130.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    14 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
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    Top Rated
    SmartwoolClassic Thermal Merino Quarter-Zip Base Layer Top - Men's
    $130.00
    49 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
    1510 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic All-Season Merino Quarter-Zip Base Layer Top - Men's
    $105.00
    7 reviews with an average rating of 4.9 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit Thermal Merino Base Layer Quarter-Zip Top - Men's
    $140.00
    18 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Women's
    $96.73
    Save 25%
    compared to  $130.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    130 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Men's
    $150.00
    193 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Women's
    $150.00
    199 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolIntraknit Thermal Merino Colorblock Quarter-Zip Base Layer Top - Women's
    $140.00
    7 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic All-Season Merino Quarter-Zip Base Layer Top - Women's
    $105.00
    3 reviews with an average rating of 4.7 out of 5 stars
    Size Type:
    Regular
    SmartwoolIntraknit Thermal Merino Base Layer Colorblock Crew - Men's
    $96.73
    Save 25%
    compared to  $130.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    15 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI OUTLET
    SmartwoolClassic Thermal Merino Colorblock Crew Base Layer Top - Women's
    $130.00
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic Thermal Merino Base Layer Crew One-Piece - Men's
    $250.00
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit AS Merino Base Layer Crew Top - Men's
    $125.00
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $81.73
    Save 28%
    compared to  $115.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    429 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    SmartwoolIntraknit Thermal Merino Base Layer Hoodie - Men's
    $180.00
    2 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
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    Terms apply
    SmartwoolThermal Merino Base Layer Hoodie - Men's
    $145.00
    3 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolIntraknit Thermal Merino Pattern Crew Base Layer Top - Women's
    $96.73
    Save 25%
    compared to  $130.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    50 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    SmartwoolIntraknit Thermal Max Merino Quarter-Zip Base Layer Top - Men's
    $155.00
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit Thermal Merino Colorblock Crew Base Layer Top - Men's
    $130.00
    15 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolIntraknit AS Merino Base Layer Crew Top - Women's
    $125.00
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic Thermal Merino Colorblock Crew Base Layer Top - Men's
    $130.00
    2 reviews with an average rating of 5.0 out of 5 stars
    Size Type:
    Regular
    SmartwoolIntraknit Thermal Max Merino Base Layer Pattern Hoodie - Women's
    $114.73
    Save 30%
    compared to  $165.00
    Use code OUTFEB26 for $20 off when you spend $100+ at REI Outlet.
    2 reviews with an average rating of 5.0 out of 5 stars
    Size Type:
    Regular
    REI OUTLET
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Kids'
    $47.93 - $65.00
    6 reviews with an average rating of 3.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolClassic Thermal Merino Mock Neck Base Layer Top - Women's
    $140.00
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    SmartwoolIntraknit Thermal Merino Base Layer Hoodie - Women's
    $180.00
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
1–30 of 35 products
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