Red Men's Underwear
(18 products)- REI Co-opHeavyweight Merino Long-Sleeve Base Layer Crew Top - Men's$69.93 - $99.95Underwear Weight:HeavyweightSize Type:Regular, Big, Tall
- REI Co-opHeavyweight Merino Base Layer Bottoms - Men'sTop Rated$69.93 - $99.95Underwear Weight:HeavyweightSize Type:Regular, Big, Tall
- REI Co-opLightweight Long-Sleeve Crew Base Layer Top - Men's$44.95Underwear Weight:LightweightSize Type:Regular, Big, Tall
- REI Co-opMerino 185 Long-Sleeve Half-Zip Base Layer Top - Men'sTop Rated$62.93 - $89.95Underwear Weight:LightweightSize Type:Regular, Big
- REI Co-opMerino 185 Long-Sleeve Base Layer Top - Men'sTop Rated$79.95Underwear Weight:LightweightSize Type:Regular, Big
- IcebreakerMerino 200 Oasis Long-Sleeve Crewe Thermal Top - Men'sTop Rated$69.93 - $120.00Underwear Weight:MidweightSize Type:Regular, Big
- REI Co-opHeavyweight Merino Base Layer Half-Zip Top - Men's$72.93 - $104.95Underwear Weight:HeavyweightSize Type:Regular, Big, Tall
- REI Co-opLightweight Crew Base Layer Top - Men'sTop Rated$14.83 - $34.95Underwear Weight:LightweightSize Type:Regular, Big, Tall
- SmartwoolClassic Thermal Merino Crew Base Layer Top - Men'sTop Rated$125.00Underwear Weight:MidweightSize Type:Regular, Big
- PatagoniaCapilene Midweight Zip-Neck Base Layer Top - Men's$68.93 - $99.00Underwear Weight:MidweightSize Type:Regular, Big
- PatagoniaCapilene Midweight Crew Base Layer Top - Men'sTop Rated$61.93 - $89.00Underwear Weight:MidweightSize Type:Regular, Big
- StanceCompression Nylon Boxer Briefs - Men's$26.73Save 31%compared to  $39.00Size Type:RegularREI OUTLET
- Arc'teryxRho LT Base Layer Bottoms - Men's$100.00Underwear Weight:LightweightSize Type:Regular, Big
- Arc'teryxRho LT Zip-Neck Base Layer Top - Men's$120.00Underwear Weight:LightweightSize Type:Regular, Big
- IcebreakerMerino 260 Tech Long Sleeve Crewe Base Layer Top - Men'sTop Rated$119.73Save 27%compared to  $165.00Underwear Weight:HeavyweightSize Type:RegularREI OUTLET
- PatagoniaCapilene Midweight Zip-Neck Long Underwear Top - Men's$73.73Save 25%compared to  $99.00Underwear Weight:MidweightSize Type:RegularREI OUTLET
- KUHLReactiv Lite Grid Quarter-Zip Base Layer Top - Men's$119.00Underwear Weight:LightweightSize Type:Regular, Big
- IcebreakerMerino 150 Tech Lite Skiing Yeti Base Layer T-Shirt - Men's$85.00Underwear Weight:LightweightSize Type:Regular
Get $130 in value
$30 in card rewards are yours when approved for the REI Co-op Mastercard by Mar 9. Plus, you can earn a $100 REI gift card after your first purchase. Terms apply.
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