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.
Imported.
View all REI Co-op Men's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | Partial-zip |
| Fabric | 92% recycled polyester/8% spandex (bluepass certified) |
| 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 bluepass certified material From a Climate Label Certified brand |
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This is a really nice base layer. The fabric is soft, comfortable, very stretchy, and seems durable. I have long arms and the sleeves easily cover them down to my hands. The thumb holes are nice for pulling the sleeves through a jacket or something else you're wearing over top. The collar is a good height - it adds to heat retention but isn't too tall or thick to constrain through the neck. The zipper provides plenty of room in the opening for easy on/off. I like the weight of the fabric. The shirt could be layered for very cold temps, or worn by itself for merely chilly weather. I can't really find anything to critique with this shirt. It's well-made, comfortable, looks good, and does its job.
The REi Co-op mid weight half zip is a great piece to wear on a nice fall day that is cool in the morning and mild in the afternoon. Can be paired with a light jacket for cooler days. I really like the light weight stretch but wish it was slightly longer in the torso. I’m a sucker for long sleeves and thumb loops as well. The color is a great share as well. Look forward to cooler weather that should be approaching soon.
Great breathable half-zip with enough stretch to keep you comfortable. I’ve worn this on hikes and ATV trips in the Snowy Range of Wyoming with just a sun hoodie underneath, and it provides the right amount of warmth while nat getting too hot. It’s not quite as breathable as some, but that makes it a bit warmer for non high output activities. Overall this is a great addition to a layering system. The stretch was just right so it moves with your body while not getting sloppy.
Great fitting base layer. Material is a good weight for under a sweater when skiing. Hidden thumb holes in sleeves are a nice touch to keep them from riding up. True to size
Looking for layers for an upcoming trip and this is perfect


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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.

