REI Co-op Lightweight Long Underwear Bottoms - Men's
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These lightweight bottoms efficiently manage moisture so you can be active and comfortable in cold conditions.
![](https://hips.hearstapps.com/vader-prod.s3.amazonaws.com/1701191223-51avaeO1sxL.jpg?crop=1xw:1.00xh;center,top&resize=980:*)
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Whether you're hiking, skiing, snowshoeing or mountaineering, men's REI Heavyweight long underwear bottoms will help you feel warmer, drier and more
![](https://www.rei.com/media/e424e9c6-4917-463d-9535-da4ee4c27f35.jpg?size=576x768)
Heavyweight Long Underwear Bottoms - Men's
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Used REI Co-op Lightweight Base Layer Bottoms
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Best Thermal Underwear for Men in 2023: 14 Pairs of Men's Long Johns
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Best Thermal Underwear for Men in 2023: 14 Pairs of Men's Long Johns
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REI Lightweight Base Layer Bottoms Review
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