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(401 products)
Products (401)
Sort: Best Match
    REI Co-opMidweight Long-Sleeve Base Layer Top - Women's
    $26.83 - $38.39
    Save 30% - 51%
    compared to  $54.95
    250 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opMidweight Long-Sleeve Base Layer Top - Men's
    $26.83 - $38.39
    Save 30% - 51%
    compared to  $54.95
    157 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
    REI Co-opMidweight Base Layer Tights - Women's
    $26.83 - $38.39
    Save 30% - 51%
    compared to  $54.95
    93 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus, Petite
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Women's
    $27.89
    Save 30%
    compared to  $39.95
    19 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
  • Sale Ends Today
    REI Co-opMidweight Base Layer Half-Zip Top - Women's
    $41.89
    Save 30%
    compared to  $59.95
    142 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
  • Sale Ends Today
    REI Co-opMidweight Base Layer Bottoms - Men's
    $38.39
    Save 30%
    compared to  $54.95
    77 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
  • Sale Ends Today
    Top Rated
    REI Co-opMidweight Base Layer Half-Zip Top - Men's
    $41.89
    Save 30%
    compared to  $59.95
    144 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big, Tall
  • Sale Ends Today
    REI Co-opLightweight Half-Zip Base Layer Top - Women's
    $31.39
    Save 30%
    compared to  $44.95
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Men's
    $27.89
    Save 30%
    compared to  $39.95
    9 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $81.73
    Save 28%
    compared to  $115.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    367 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
    REI OUTLET
    tasc PerformanceElevation Merino T-Shirt - Men's
    $49.73
    Save 37%
    compared to  $79.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    38 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Men's
    $20.89
    Save 30%
    compared to  $29.95
    17 reviews with an average rating of 4.5 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
    178 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Women's
    $20.89
    Save 30%
    compared to  $29.95
    10 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    SmartwoolClassic All-Season Merino Long-Sleeve Base Layer Top - Women's
    $66.93 - $90.00
    119 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $81.73
    Save 28%
    compared to  $115.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    247 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Plus, Regular
    REI OUTLET
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Men's
    $27.89
    Save 30%
    compared to  $39.95
    11 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Infants'/Toddlers'
    $13.89
    Save 30%
    compared to  $19.95
    8 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Crew Base Layer Top - Infants'/Toddlers'
    $13.89
    Save 30%
    compared to  $19.95
    10 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    tasc PerformanceElevation Merino Base Layer Bottoms - Women's
    $49.73
    Save 37%
    compared to  $79.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    53 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Base Layer Tights - Women's
    $27.89
    Save 30%
    compared to  $39.95
    7 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Top Rated
    REI Co-opMidweight Base Layer Bottoms - Kids'
    $23.93 - $34.95
    8 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    Top Rated
    REI Co-opMidweight Base Layer Crew Top - Kids'
    $23.93 - $34.95
    5 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Half-Zip Base Layer Top - Men's
    $31.39
    Save 30%
    compared to  $44.95
    5 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    SmartwoolClassic Thermal Merino Base Layer Bottoms - Women's
    $115.00
    736 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Men's
    $85.73
    Save 25%
    compared to  $115.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    276 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Kids'
    $20.89
    Save 30%
    compared to  $29.95
    9 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    tasc PerformanceElevation Merino Base Layer Bottoms - Men's
    $49.73
    Save 37%
    compared to  $79.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    31 reviews with an average rating of 3.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    Top Rated
    SmartwoolClassic Thermal Merino Crew Base Layer Top - Women's
    $115.00
    1149 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
  • Sale Ends Today
    Top Rated
    REI Co-opLightweight Base Layer Crew Top - Kids'
    $20.89
    Save 30%
    compared to  $29.95
    12 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
1–30 of 401 products
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