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Underwear

(560 products)
Products (560)
Sort: Best Match
    IcebreakerMerino Base Layer Leggings - Women's
    $149.73
    Save 25%
    compared to  $200.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    3 reviews with an average rating of 4.3 out of 5 stars
    Size Type:
    Regular
    REI OUTLET
    SmartwoolIntraknit Active Base Layer Crew Shirt - Men's
    $74.73
    Save 32%
    compared to  $110.00
    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:
    Big, Regular
    REI OUTLET
    SmartwoolClassic All-Season Merino Quarter-Zip Base Layer Top - Women's
    $95.00
    1 reviews with an average rating of 5.0 out of 5 stars
    Size Type:
    Regular
    Top Rated
    Black DiamondSolution 150 Merino Base Layer Bottoms - Women's
    $79.73
    Save 27%
    compared to  $110.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    31 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    Top Rated
    IcebreakerMerino 200 Oasis Long-Sleeve Half-Zip Thermal Base Layer Top - Women's
    $84.73
    Save 26%
    compared to  $115.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    20 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Plus, Regular
    REI OUTLET
    RONHILLShort Underwear - Women's
    $23.73
    Save 32%
    compared to  $34.95
    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
    Size Type:
    Regular
    REI OUTLET
    Top Rated
    The North FaceSummit Series Pro 120 Crew Base Layer Top - Women's
    $90.00
    13 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Ultralightweight
    Size Type:
    Regular, Plus
    StanceCurren Poly Boxer Briefs - Men's
    $18.73
    Save 25%
    compared to  $25.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    2 reviews with an average rating of 4.5 out of 5 stars
    Size Type:
    Regular
    REI OUTLET
    Free CountryMicrotech Heat Cocaber Base Layer Bottoms - Women's
    $34.73
    Save 30%
    compared to  $50.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    StanceTwo Tone 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
    StanceNavy Mash Wholester Boxer Briefs - Men's
    $26.73
    Save 23%
    compared to  $35.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Size Type:
    Regular
    REI OUTLET
    Ortovox120 Comp Light Base Layer Hoody - Men's
    $59.83 - $120.00
    2 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SaxxTraining Shorts Liner - Men's
    $29.73
    Save 25%
    compared to  $40.00
    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
    Size Type:
    Regular
    REI OUTLET
    Terramar1.0 All-Season Lightweight Merino Wool T-Shirt - Women's
    $34.73
    Save 30%
    compared to  $50.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Men's
    $130.00
    188 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    StancePop End 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
    Arc'teryxRho Merino Wool Zip-Neck Base Layer Top - Men's
    $98.83
    Save 29%
    compared to  $140.00
    11 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Big
    Top Rated
    IcebreakerMerino 200 Oasis Base Layer Leggings with Fly - Men's
    $105.00
    53 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Helly HansenH1 Pro Lifa Seamless Half-Zip Base Layer Top - Men's
    $96.73
    Save 35%
    compared to  $150.00
    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
    Top Rated
    SmartwoolIntraknit Thermal Merino Base Layer Quarter-Zip Top - Men's
    $140.00
    11 reviews with an average rating of 4.9 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    Top Rated
    IcebreakerMerino 200 Oasis Long-Sleeve Crewe Thermal Top - Men's
    $78.73
    Save 25%
    compared to  $105.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    64 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    Terramar2.0 Cloud Nine Midweight Performance Thermal Turtleneck - Women's
    $32.73
    Save 31%
    compared to  $48.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
  • Sale Ends Aug 28
    SmartwoolIntraknit Active Base Layer Bottoms - Women's
    $55.00
    Save 50%
    compared to  $110.00
    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
    SmartwoolClassic Thermal Merino Colorblock Crew Base Layer Top - Women's
    $130.00
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    Kari TraaSmekker Base Layer Pants - Women's
    $83.73
    Save 30%
    compared to  $120.00
    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:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    Kari TraaLune Long-Sleeve Base Layer Top - Women's
    $41.73
    Save 35%
    compared to  $65.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    2 reviews with an average rating of 3.0 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular
    REI OUTLET
    SmartwoolIntraknit Bikini Underwear - Women's
    $34.00
    5 reviews with an average rating of 1.8 out of 5 stars
    Size Type:
    Regular
    PatagoniaCapilene Midweight Zip-Neck Base Layer Top - Women's
    $99.00
    28 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    CraftCore Dry Active Comfort Base Layer Pants - Men's
    $32.73
    Save 34%
    compared to  $49.95
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    2 reviews with an average rating of 2.5 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    PatagoniaCapilene Thermal Weight Long Underwear Crew Top - Men's
    $99.00
    10 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular, Big
Sort: Best Match

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