How to Choose Base Layers

A good day outdoors starts with a good base layer. This soft, synthetic top from REI Co-op provides midweight warmth for comfortable layering on cold days. It has thumbholes and a half-zip front.
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Imported.
View all REI Co-op Women's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | Partial-zip |
| Fabric | 92% recycled polyester/8% spandex (bluesign® approved) |
| Sun-Protective Fabric | Yes |
| UPF Rating | 50+ |
| Moisture Wicking | Yes |
| Underwear Weight | Midweight |
| Sleeve Length | Long Sleeve |
| Thumbholes | Yes |
| Gender | Women's |
| Sustainability | Fair Trade Certified™ Factory Contains recycled materials Contains materials that meet the bluesign® criteria From a Climate Label Certified brand |
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Long sleeve quarter zips are an essential part of my wardrobe - outside and inside! This long sleeve is very unassuming. Even though it is primarily polyester with some spandex, it feels and looks like a shirt made primarily with natural fibers! I like my clothes to fit more ‘relaxed’ so I got this in XL (5’9”, 178lbs) and the fit is perfect! Arms and body length are great and to top off it has well placed thumb holes! Wore it a few times in cool Wisconsin fall days walking the dogs and visiting WI Sheep & Wool Festival. Warmth was good by itself at low 60s. When in 50s, needed another layer it as it is pretty thin. It is a nice teal color and I could totally get away with wearing this at work. I’ll be getting more colors!
This top is super versatile and while I only wore it as a single layer, I can see myself using it as a base layer in the colder months. It’s lightweight and comfortable, with just a little bit of stretch. I also love the thumb holes that are usable but discreet.


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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.

