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Underwear

(560 products)
Products (560)
Sort: Best Match
  • Sale Ends Aug 28
    Top Rated
    Icebreaker125 ZoneKnit Merino Long-Sleeve Crewe Thermal Top - Men's
    $62.50
    Save 50%
    compared to  $125.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    6 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Ultralightweight
    Size Type:
    Regular, Big
    REI OUTLET
    PatagoniaCapilene Thermal Weight Long Underwear Crew Top - Women's
    $99.00
    9 reviews with an average rating of 3.2 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular
    StanceLucias Floral Boxer Briefs - Men's
    $19.73
    Save 26%
    compared to  $27.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Size Type:
    Regular
    REI OUTLET
    SmartwoolClassic Thermal Merino Base Layer Hoodie - Kids'
    $51.73
    Save 31%
    compared to  $75.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    3 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    Kari TraaKlara High-Waisted Base Layer Pants - Women's
    $66.73
    Save 25%
    compared to  $90.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    1 reviews with an average rating of 3.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    StancePedlz Fallin Boxer Briefs - Men's
    $22.73
    Save 24%
    compared to  $30.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Size Type:
    Regular
    REI OUTLET
    Top Rated
    Helly HansenLifa Merino Midweight Half-Zip Base Layer Top - Men's
    $110.00 - $115.00
    5 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    Top Rated
    IcebreakerMerino 260 Tech Thermal Base Layer Leggings - Women's
    $93.73
    Save 25%
    compared to  $125.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    22 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Plus
    REI OUTLET
    Arms of Andes300 Lightweight Alpaca Wool Pullover Base Layer Hoodie - Women's
    $140.00
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Icebreaker200 Oasis Sonebula Long-Sleeve Crewe Base Layer Top - Women's
    $89.73
    Save 25%
    compared to  $120.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
  • Sale Ends Aug 28
    ArtilectFlatiron 185 Base Layer Leggings - Women's
    $80.00
    Save 50%
    compared to  $160.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    1 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    Icebreaker200 ZoneKnit Thermal Base Layer Leggings - Women's
    $109.73
    Save 26%
    compared to  $150.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    4 reviews with an average rating of 4.8 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    The North FaceFD Pro 160 Base Layer Tights - Women's
    $70.00
    47 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Plus
    PatagoniaCapilene Thermal Weight Boot-Length Long Underwear Bottoms - Women's
    $85.00
    6 reviews with an average rating of 3.5 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular
    Kari TraaRose Capri High-Waist Base Layer Bottoms - Women's
    $110.00
    0 reviews
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular
    StanceSunrise Boxer Briefs - Men's
    $18.73
    Save 25%
    compared to  $25.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Size Type:
    Regular
    REI OUTLET
  • Sale Ends Aug 28
    StanceTakawitz Boxer Briefs - Men's
    $15.00
    Save 50%
    compared to  $30.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    2 reviews with an average rating of 5.0 out of 5 stars
    Size Type:
    Regular, Big
    REI OUTLET
    Icebreaker200 ZoneKnit Merino Thermal Base Layer Leggings - Men's
    $109.73
    Save 26%
    compared to  $150.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    6 reviews with an average rating of 4.2 out of 5 stars
    Size Type:
    Regular, Big
    REI OUTLET
    Ortovox230 Competition Long Base Layer Pants - Men's
    $100.00
    1 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    StanceOde To Cali Boxer Briefs - Men's
    $19.73
    Save 26%
    compared to  $27.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Size Type:
    Regular
    REI OUTLET
    Kari TraaAlma Base Layer Pants - Women's
    $52.73
    Save 24%
    compared to  $70.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Ultralightweight
    Size Type:
    Regular
    REI OUTLET
    SmartwoolClassic Thermal Merino Half-Zip Base Layer Hoodie - Women's
    $145.00
    0 reviews
    Size Type:
    Regular
    SmartwoolIntraknit Thermal Max Merino Quarter-Zip Base Layer Top - Men's
    $155.00
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
  • Sale Ends Aug 28
    ArtilectDarkhorse 185 Zoned Crew Base Layer Top - Women's
    $80.00
    Save 50%
    compared to  $160.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    1 reviews with an average rating of 2.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    Kari TraaFierce Base Layer Pants - Women's
    $46.73
    Save 29%
    compared to  $66.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    IcebreakerSiren Sweetheart Long Underwear Top - Women's
    $85.00
    22 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    New arrival
    SmartwoolClassic Thermal Merino Base Layer Crew One-Piece - Women's
    $250.00
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    New arrival
    FjallravenBergtagen Merino 190 T-Shirt - Men's
    $100.00
    0 reviews
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    StanceSanta Rips Boxer Briefs - Men's
    $22.73
    Save 35%
    compared to  $35.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Size Type:
    Regular
    REI OUTLET
    CraftActive Intensity Zip Base Layer Top - Women's
    $54.73
    Save 31%
    compared to  $79.95
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    3 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
Sort: Best Match

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