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 | Partial-zip |
| Fabric | 100% merino wool |
| Sun-Protective Fabric | Yes |
| UPF Rating | 30 |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Lightweight |
| Sleeve Length | Long Sleeve |
| Gender | Men's |
| Sustainability | Fair Trade Certified™ Factory From a Climate Label Certified brand |
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What an awesome wool product! I love wearing wool and especially while being active. This garment breathes exceptionally well and wicks great! It kept me cool during the warmer days and sun off my arms and kept me warm during the chilly Colorado nights. I have worn it for close to three weeks without washing it and I don't feel the need to wash it yet. It's held up well and is super comfortable. The flat rolled seams do not irritate your skin and it's not itchy at all. It's extremely soft and light and I like the dark blue color on it. It's convenient to be able to roll up the sleeves and they don't constrict your arms if it stays rolled up. The wool is stretchy and easy to take on and off with the zip. I have worn this at night and during the day while walking. I backpack a bit and can't wait to take this as another warm layer for the trail on future trips. Highly recommend!
Love how soft yet durable this shirt feels. I have been wearing it for my base layer on nighttime and early morning hikes for a few days now and absolutely love it. It stretches and moves with my body and doesn’t seem to hold onto odors at all. I will def be picking up another one or two of these.


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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.

