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Long Underwear
(366 products)Products (366)
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- Arc'teryxRho Base Layer Hoody - Women'sTop Rated$96.73Save 19%compared to  $120.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Helly HansenMerino Wool Base Layer Set - Kids'$75.73Save 36%compared to  $120.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Helly HansenGraphic Lifa Merino Base Layer Set - Kids'$74.73Save 32%compared to  $110.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Kari TraaLucie Half-Zip Base Layer Top - Women's$67.73Save 24%compared to  $90.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Kari TraaAlma Hood Base Layer Top - Women's$59.73Save 25%compared to  $80.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- IcebreakerMerino 260 Tech Long-Sleeve Half-Zip Thermal Base Layer Top - Kids'$52.73Save 29%compared to  $75.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- IcebreakerMerino 200 ZoneKnit Long-Sleeve Half-Zip Thermal Base Layer Top - Women's$119.73Save 25%compared to  $160.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Women's$96.73Save 25%compared to  $130.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- IcebreakerMerino 260 Tech Long Sleeve Crewe Base Layer Top - Men'sTop Rated$119.73Save 27%compared to  $165.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- IcebreakerMerino 125 ZoneKnit Long-Sleeve Half-Zip Base Layer Top - Men'sTop Rated$99.73Save 26%compared to  $135.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Icebreaker125 ZoneKnit Merino Long-Sleeve Crewe Thermal Top - Men'sTop Rated$93.73Save 25%compared to  $125.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Kari TraaLilja Long-Sleeve Base Layer Top - Women's$49.73Save 24%compared to  $66.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolIntraknit Thermal Max Merino Base Layer Pattern Hoodie - Women's$123.73Save 25%compared to  $165.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolIntraknit Thermal Merino Pattern Crew Base Layer Top - Women's$96.73Save 25%compared to  $130.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolClassic Thermal Merino Base Layer Quarter-Zip - Men'sTop Rated$89.73Save 25%compared to  $120.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolClassic Thermal Merino Crew Base Layer Top - Kids'$44.73Save 31%compared to  $65.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SaxxRoast Master Midweight Long-Sleeve Crew Base Layer Top - Men's$52.73Save 29%compared to  $75.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolClassic Thermal Merino Base Layer Quarter-Zip - Kids'$51.73Save 26%compared to  $70.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolIntraknit Thermal Merino Base Layer Colorblock Crew - Men's$96.73Save 25%compared to  $130.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Men's$92.73Save 28%compared to  $130.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Icebreaker125 ZoneKnit Long-Sleeve Crewe Base Layer Top - Men's$125.00
- PatagoniaCapilene Midweight Zip-Neck Base Layer Top - Women's$74.73Save 24%compared to  $99.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- CraftCORE Dry Active Comfort Base Layer Top - Men's$39.73Save 38%compared to  $64.95Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- NRSH2Core Lightweight Union Suit - Men's$109.95
- The North FaceSummit Series Pro 120 Crew Base Layer Top - Women'sTop Rated$100.00
- SmartwoolClassic Thermal Merino Base Layer Hoodie - Kids'$51.73Save 31%compared to  $75.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- IcebreakerMerino Blend 260 ZoneKnit Seamless Long-Sleeve Crew Base Layer Top - Women's$150.00
- Icebreaker260 ZoneKnit Long-Sleeve Crewe Thermal Top - Men'sTop Rated$165.00
- IcebreakerMerino 260 Tech Long-Sleeve Turtleneck Base Layer - Men'sTop Rated$135.00
- Arc'teryxRho Heavyweight Zip-Neck Base Layer Top - Men's$112.73Save 19%compared to  $140.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
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