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 | Short Sleeve |
| Gender | Women's |
| Sustainability | Fair Trade Certified™ Factory From a Climate Label Certified brand |
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Excellent quality product. Wore this on an early morning hike, and my core was a comfortable temperature the entire time even when my legs were cold or hot. The hike started off cool and I was wearing a long sleeve shirt over this t-shirt. When I got to the top, I took off the long sleeve for the descent and saw I had actually been sweating quite a lot on the way up. The shirt never felt damp or sticky, which tells me it does a great job of wicking away moisture. It has a comfortable fit and feels true to size - I have a 40” chest and 32” waist and ordered a Large. It is semi-fitted without feeling restrictive, and the fabric is soft against the skin. I appreciate that it has a generous length in front and back. The seams inside (and outside) the garment are constructed in a way that they are very low profile and smooth/comfortable as well - no risk of chafing on them. There is a small loop at the back of the neck where you could hang it on something to air out or dry off after use. This would be a great shirt for camping, outdoor activities, or traveling - any activity where you want your clothing to help regulate your body temperature and wick away sweat. I plan to wear this next time I fly as I’m always too cold or hot on planes.


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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.

