How to Choose Base Layers

Get ready for adventures in the cold with our warmest merino base layer bottoms yet. These REI Co-op heavyweight, high-rise leggings are made with 100% merino wool that's supersoft on the skin.
Imported.
View all REI Co-op Women's Base Layer Bottoms| Best Use | Multisport |
|---|---|
| Fabric | 100% merino wool |
| Sun-Protective Fabric | Yes |
| UPF Rating | 50+ |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Heavyweight |
| Inseam (in.) | 28 inches |
| Gender | Women's |
| Sustainability | Fair Trade Certified™ Factory From a Climate Label Certified brand |
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So soft and silky. These kept me comfortable on a hike that was warm, then rainy, then cold and windy, on their own, but the fabric is so smooth that they'll be a great baselayer too. Not itchy at all and held up perfectly well to normal laundry. They do run big, but even being a little loose on me, I never felt them sagging or falling down. The knit is very tight and opaque, especially compared to other baselayers I own.
These long John’s are so soft and “buttery smooth” to quote another reviewer. They are long enough for me (for once!). I read a lot about polyester base layers but I couldn’t bring myself to pay almost the same price for plastic (yes, polyester is essentially plastic), when I could have this ultra soft Merino wool. Well done, REI. These fit true to size or just slightly big. I am 5’7”, 149 lbs with 40” hips and I bought my usual Medium.


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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.

