REI Co-op Midweight Long-Sleeve Base Layer Top - Men's
![REI Co-op Midweight Long-Sleeve Base Layer Top - Men's](https://www.rei.com/media/ab86a3af-e11f-4c42-921a-63b8c0a7c16e.jpg?size=576x768)
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Base Layers, Thermal Underwear & Long Underwear
REI Co-op Midweight Base Layer Half-Zip Top - Men's
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Long Sleeve Base Layers
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REI Co-op Midweight Base Layer Crew Top - Men's
![](https://www.rei.com/media/9d0e37e9-73c6-433c-b6ab-be14acd5977f.jpg?size=576x768)
Odlo Natural + Kinship Warm Crew Base Layer Top - Men's
![](https://i.ytimg.com/vi/OIu3c3-fYfY/maxresdefault.jpg)
REI Co-op Merino Midweight Base Layer Long-Sleeve Crew Top - Men's
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