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  • Durable polyester/spandex blend wicks moisture and dries quickly
  • Mineral-based LAVA XL™ finish keeps fabric odor-free
  • Flatseam construction, raglan sleeves and side gussets keep you comfortable as you move
  • Droptail hem won't expose your back when you bend over and settles nicely under a pack's hipbelt
  • UPF 50 sun protection
  • Fitted

Made in USA.

View all REI Co-op Men's Long Underwear Tops

REI membership


Best Use Multisport
Shirt Style Crew
Fabric 89% polyester/11% spandex
Sun-Protective Fabric Yes
UPF Rating 50
Moisture Wicking Yes
Quick Drying Yes
Sleeve Length Long Sleeve
Gender Men's

Size chart

Sizing notes

SHORT: Some pants are available in short sizes, which generally means an inseam that is 2.5 inches shorter than regular sizes. TALL: Some pants, shirts, jackets and parkas are available in tall sizes, which generally means an inseam that is 3 inches longer and a rise that is 1 inch longer, a shirt or jacket body that is 2 inches longer, a parka body that is 2.5 inches longer and sleeves that are 2.5 inches longer than regular sizes.

Rated 5 out of 5 by from Like wearing a rainbow Used these bad boys whilst snowboarding up in the Wasatch front. They fit well. The fabric is soft like your favorite puppy but strong and resilient like bull. I love them. The only reason I took them off was because it's still not socially acceptable to roam about in my underwear. I highly recommend you get yourself a pair.
Date published: 2017-01-06
Rated 5 out of 5 by from Great top for running in cold Warm top for running in the cold. Fits snug (took a medium vs. normal large) and feels great against your skin. Drys quickly and stays warm even after standing around after activity. Bought a second one for my son.
Date published: 2017-01-11
Rated 4 out of 5 by from Good, not great, fit The fit on these is pretty decent. Snug in the arms and chest but noticeably looser in the lower chest and trunk area. Breathability and warmth are both good.
Date published: 2017-01-13
Rated 5 out of 5 by from Backpacking Bought for nights during backpacking trip on AT. Temps were in the low 20's and it was a comfortable, warm, lightweight base layer. Very satisfied!
Date published: 2017-04-06
Rated 2 out of 5 by from Material is nice. HUGE neck. Material is great. Overall size runs larger than other REI shirts. The hole for the neck is enormous and makes the shirt look ridiculous. Very odd.
Date published: 2017-02-03
Rated 5 out of 5 by from Well worth it I bought this for my trip to Iceland and it worked very well. Great as a second layer.
Date published: 2017-01-12
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