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Outdoor Underwear
(515 products)Products (515)
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- IcebreakerMerino 200 Oasis Long-Sleeve Crewe Thermal Top - Men'sTop Rated$78.73Save 25%compared to  $105.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Arc'teryxRho Heavyweight Base Layer Bottoms - Men'sTop Rated$59.83Save 50%compared to  $120.00
- IcebreakerMerino 200 Oasis Long-Sleeve Crewe Thermal Top - Women'sTop Rated$105.00
- REI Co-opMerino 185 Base Layer Top - Men's$48.93 - $69.95
- SmartwoolClassic All-Season Merino Quarter-Zip Base Layer Top - Women's$95.00
- Outdoor ResearchVantage Printed Crop Top$38.73Save 29%compared to  $55.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolIntraknit Strappy Bra$75.00
- StanceSanta Rips Boxer Briefs - Men's$22.73Save 35%compared to  $35.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Outdoor ResearchVantage Bra$39.73Save 27%compared to  $55.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- PatagoniaCapilene Thermal Weight Zip-Neck Long Underwear Top - Women's$109.00
- REI Co-opHeavyweight Merino Base Layer Half-Zip Top - Men's$49.83 - $104.95
- Arc'teryxRho Merino Wool Crew Neck Base Layer Top - Men'sTop Rated$59.83 - $120.00
- PatagoniaCapilene Midweight Crew Base Layer Top - Women'sTop Rated$89.00
- Free CountryForce Grid Fleece Base Layer Top - Women's$34.73Save 36%compared to  $55.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- prAnaChakara Crop Top - Women's$52.73Save 29%compared to  $75.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- CraftCORE Dry Active Comfort Base Layer Top - Women's$39.73Save 38%compared to  $64.95Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- StanceInvestor Boxer Briefs - Men's$22.73Save 24%compared to  $30.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- IcebreakerMerino 260 Vertex Long-Sleeve Crewe Natural Shades Base Layer Top - Women's$104.73Save 25%compared to  $140.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolClassic Thermal Merino Quarter-Zip Base Layer Top - Men'sTop Rated$120.00
- SmartwoolClassic Thermal Merino Crew Base Layer Top - Men'sTop Rated$85.73Save 25%compared to  $115.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- REI Co-opMidweight Crew Base Layer Top - Toddlers'Top Rated$24.95
- REI Co-opLightweight Half-Zip Base Layer Top - Men's$44.95
- Royal RobbinsReadyDry 7" Boxer Briefs - Men's$21.73Save 27%compared to  $30.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- REI Co-opLightweight Base Layer Tights - Women'sTop Rated$39.95
- SmartwoolIntraknit Strappy Bra$65.00
- BrooksRacerback 2.0 Sports Bra$75.00
- Icebreaker260 Tech Long-Sleeve Crewe Base Layer Top - Women'sTop Rated$125.00
- StanceBarnabe Wholester Boxer Briefs - Men's$24.73Save 29%compared to  $35.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- BurtonMidweight Base Layer Pants - Women's$19.83Save 69%compared to  $64.95
- SmartwoolIntraknit Racerback Bra$65.00
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