How to Choose Base Layers

Outfit yourself for adventure with this 100% merino wool base layer top from REI Co-op. The breathable, ultrafine wool naturally resists odors and pilling. Flat seams are comfortable on the skin.
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Imported.
View the REI Co-op Merino 185 Product LineView all REI Co-op Men's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | T-shirt |
| Fabric | 100% merino wool |
| Sun-Protective Fabric | Yes |
| UPF Rating | 30 |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Lightweight |
| Sleeve Length | Short Sleeve |
| Gender | Men's |
| Sustainability | Fair Trade Certified™ Factory From a Climate Label Certified brand |
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Comfortable, no itch, wool. Stitching seems good. I am usually a large, this is a bit large for a large
Great merino wool shirt, if you don’t like it baggy I would size down. In a medium in the arc’teryx version of this shirt and got a small in this one and fits perfect.


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From feedback to field testing, all of our gear is dialed-in by REI Co-op members. Their adventures informed every stitch and detail—making for better, longer-lasting gear.

