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 Women'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 | Long Sleeve |
| Gender | Women's |
| Sustainability | Fair Trade Certified™ Factory From a Climate Label Certified brand |
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Decent fit although a little rigid feeling. I’m new to wearing merino wool but found this top very itchy. It is a bit rough feeling and I can’t imagine hiking in this.
Cozy layer, easily fits under full zip jacket. 5', 4", 130lbs, size M
Fits well, excellent warmth for any season, love the soft wool


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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.

