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  • Polartec® Power Wool™ blends wool on the inside and synthetic on the outside to provide excellent temperature regulation, moisture management and durability
  • Wool is naturally odor-resistant
  • Flatlock seams add extra elasticity and prevent abrasion
  • Lightweight stretch fabric provides comfort and mobility
  • Rated UPF 35+ for sun protection
  • Athletic fit


View all Mammut Men's Long Underwear Tops

REI membership


Best Use Multisport
Shirt Style Crew
Fabric 66% polyester/34% wool
Sun-Protective Fabric Yes
UPF Rating 35
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Lightweight
Sleeve Length Short Sleeve
Gender Men's

Size chart

Rated 4 out of 5 by from Warmer than a typical t-shirt I wore the shirt twice. It's warmer than a typical t-shirt, and that's why I bought it. It's pretty comfortable, soft, and falls nice. The fit was just a little odd in the back of the neck. The length was an inch or so longer than I expected, making it snug below the waist; but it's just like the photo.
Date published: 2017-05-08
Rated 5 out of 5 by from Perfect light layer Great fit and feel, and is a convenient lightweight extra layer
Date published: 2017-02-25
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