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.
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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I wore this shirt on the first cool day in the PNW to do some ridiculous yardwork. Best shirt for sweating and movement. The cut prevented the shirt from riding up (especially the gussets under the arms/side torso), and I had full mobility. It's so so soft and washed very easily with no change to the fabric. It's thin enough to wear underneath another layer (I wore it under a sweatshirt), but you wouldn't be able to see that in a pic, so where's the fun in that? The color is a blue-ish purple. In the shade it looks more purple, in full light the blue tones are more apparent.
Shirt is a nice, soft blue color. Material is a nice medium weight and decently soft and smooth for merino wool. It looks good during exercise and casual wear, and it holds up well after washing. Doesn’t wrinkle easily.
I’ve worn this shirt on bike rides (10-20 miles) this fall. The fit is ok, not great for my body (I’m 5’7, 155 lbs, wearing the medium). The neck hole runs a little small and it’s longer on the bottom than I usually wear (but on the plus side it doesn’t ride ride up when I’m on the bike or have a backpack on!). It’s a little bit hotter than my other wool blend shirts that I have for outdoor activities, but still a solid base layer.
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.

