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(563 products)
Products (563)
Sort: Best Match
    Arms of Andes160 Ultralight Alpaca Wool Crew Neck Base Layer T-Shirt - Women's
    $75.00
    2 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Ultralightweight
    Size Type:
    Regular
    Helly HansenLifa Active Base Layer Bottoms - Women's
    $39.73
    Save 27%
    compared to  $55.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
  • Sale Ends Aug 28
    Helly HansenLIFA Merino Midweight Balaclava Base Layer Hoodie - Women's
    $74.99
    Save 50%
    compared to  $150.00
    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
    Ortovox120 Comp Light Short Base Layer Pants - Men's
    $70.00
    3 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    StanceTubeular Boxer Briefs - Men's
    $18.73
    Save 25%
    compared to  $25.00
    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
    Size Type:
    Regular
    REI OUTLET
    Icebreaker125 ZoneKnit Crewe Base Layer Shirt - Men's
    $84.73
    Save 26%
    compared to  $115.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    6 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI OUTLET
    Icebreaker125 ZoneKnit Thermal Base Layer Leggings - Women's
    $86.73
    Save 30%
    compared to  $125.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    StanceThe Vacationeer Boxer Briefs - Men's
    $19.73
    Save 26%
    compared to  $27.00
    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
    Size Type:
    Regular
    REI OUTLET
    Top Rated
    Arms of Andes300 Lightweight Alpaca Wool Base Layer Leggings - Women's
    $105.00
    8 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Arms of Andes300 Lightweight Alpaca Wool Base Layer Leggings - Men's
    $115.00
    12 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
  • Sale Ends Aug 28
    Top Rated
    Icebreaker200 ZoneKnit Long-Sleeve Crewe Base Layer Thermal Top - Men's
    $74.99
    Save 50%
    compared to  $150.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    7 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI OUTLET
    Arms of Andes300 Lightweight Alpaca Wool Half-Zip Base Layer Top - Men's
    $145.00
    14 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    KUHLReactiv Lite Grid Quarter-Zip Base Layer Top - Men's
    $119.00
    1 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    Sweaty BettyHigh-Neck Jacquard Base Layer Top - Women's
    $82.73
    Save 29%
    compared to  $118.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    23 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    The North FaceSummit Pro 120 Base Layer Tights - Women's
    $100.00
    32 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    Kari TraaEmbla Wool Boxer Briefs - Women's
    $40.00
    1 reviews with an average rating of 1.0 out of 5 stars
    Size Type:
    Regular
    StancePoppyland Boxer Briefs - Men's
    $18.73
    Save 25%
    compared to  $25.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    1 reviews with an average rating of 1.0 out of 5 stars
    Size Type:
    Regular
    REI OUTLET
    Arc'teryxRho LT Base Layer Bottoms - Men's
    $79.73
    Save 20%
    compared to  $100.00
    11 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI OUTLET
  • Sale Ends Aug 28
    SpraywayEffra Hoody Base Layer Top - Women's
    $34.89
    Save 50%
    compared to  $69.95
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Heavyweight
    Size Type:
    Regular
    REI OUTLET
    Arms of Andes160 Ultralight Alpaca Wool Crewneck Base Layer T-Shirt - Men's
    $80.00
    5 reviews with an average rating of 3.2 out of 5 stars
    Underwear Weight:
    Ultralightweight
    Size Type:
    Regular
    TerramarC-Suite Fusion Thermal Pants - Women's
    $42.73
    Save 34%
    compared to  $65.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    Helly HansenVerglas Half-Zip Top - Women's
    $63.73
    Save 25%
    compared to  $85.00
    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
    ArtilectBoulder 125 Crew Long-Sleeve Base Layer Top - Women's
    $75.73
    Save 36%
    compared to  $120.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    1 reviews with an average rating of 1.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    CraftCore Dry Active Comfort Long-Sleeve Base Layer Jersey - Kids'
    $38.73
    Save 40%
    compared to  $64.95
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    Helly HansenLIFA ACTIVE Graphic Crew Base Layer Top - Women's
    $42.73
    Save 34%
    compared to  $65.00
    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
    SmartwoolIntraknit Thermal Merino Base Layer Colorblock Crew - Men's
    $96.73
    Save 25%
    compared to  $130.00
    Members use code LABORDAY2025 for an extra 20% off at REI Outlet
    11 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Big
    REI OUTLET
    Icebreaker200 Oasis Sonebula Base Layer Leggings - 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 3.0 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    REI OUTLET
    SeirusHeatwave Body Mapped Full-Length Base Layer Bottoms - Women's
    $59.83
    Save 50%
    compared to  $119.95
    0 reviews
    Underwear Weight:
    Midweight
    Size Type:
    Regular
    Top Rated
    IcebreakerMerino 260 Tech Long-Sleeve Half-Zip Base Layer Top - Women's
    $135.00
    26 reviews with an average rating of 4.7 out of 5 stars
    Underwear Weight:
    Midweight
    Size Type:
    Regular, Plus
  • Sale Ends Aug 28
    Top Rated
    Icebreaker125 ZoneKnit Merino Long-Sleeve Crewe Thermal Top - Men's
    $62.49
    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
Sort: Best Match

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