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. Thumbholes add a cozy feel.
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Imported.
View all REI Co-op Men's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | T-shirt |
| 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 | Men'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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I received this REI midlayer for free in exchange for my honest review. I got it during the summer, so I haven't been able to test it in true cold weather yet, but I'm impressed so far. The material is dense, warm, and feels very well made. Even in 80–85 degree weather, I was able to wear it around the water, on trails, and in the fields without feeling overly uncomfortable. It breathes better than I expected for something this substantial. I also really like the flat stitching, lack of tags, longer sleeves, and overall fit. Nothing rubbed or felt irritating, and the green color looks great in person. My only question is long-term odor retention, since that can be an issue with synthetic materials. I haven't had it long enough to judge that fairly yet. Overall, this feels like a durable, comfortable, thoughtfully made midlayer that should be excellent for colder weather.
This is a great layer. I really like the weight and feel, and it's much warmer than I expected. I got a size larger than normal to layer more comfortably, and for a little more comfort when sleeping. Great color for cruising through the forest and fitting in with the setting. Good breathability, and the seams dont rub under my pack straps. The weight was also nice cutting brush and climbing rock.
A solid, mid-weight base layer that is comfortable to wear. Seams are well constructed and do not cause irritation or rubbing. The thumb loops on the sleeve cuffs are among the best I've ever come across as they blend in well - basically invisibly - with the cuffs when not in use. Odor control of the material is very good, allowing repeated use across multiple days without becoming obnoxious.


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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.

