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  • Silkweight Phasic™ SL polyester fabric speeds dry time, improves moisture transfer and elevates comfort
  • Gusseted underarms facilitate ergonomic freedom
  • Flatlock construction improves comfort against your skin
  • Next-to-skin fit aids thermal efficiency and moisture transfer
  • Anatomic shaping for fit and comfort


View all Arc'teryx Men's Long Underwear Tops

REI membership


Best Use Multisport
Shirt Style Crew
Fabric Polyester
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Ultralightweight
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 inches shorter than regular sizes. TALL: Some pants are available in tall sizes, which generally means an inseam that is 3 inches longer than regular sizes.

Rated 4 out of 5 by from Wicks very, very well. This is my primary base layer when the predicted activity level leads me to believe I may generate a little moisture on my skin. It picks up that moisture and carries it into the fabric so well, you might not even notice you were sweating. When it's moist, it clings to your skin very well, so well it will not slide it around. The only negative I can say, is it is EXTREMELY fragile. I would give it a durability rating of 2/10. It's almost as fragile as pantyhose. The very first time I used it, I didn't realize how sticky it would be against my skin, and I didn't have the seams positioned perfectly. When I went to pull on the sleeve, I popped some stitching out of the section that is reinforced around the sleeve. This shows they thought ahead in the design and put a little extra there. No big deal right? I went to cut back the threads and melt the tails off to stop the seam from running, but that was a super bad idea. Before I even applied enough heat from the bic to melt back the threads, it melted the material in the shirt. My bad. The only way I have found to take it off without letting it totally air out and dry off is to pull it by the bottom till it's all clumped up around your chest, then reach back behind your head and pull it over your head while inverting it. Like I do my neoprene wetsuits. All in all, I'm debating on whether I will buy another, as it is a bit expensive for how fragile it is. I don't see myself getting much life out of it, though it works very well. This is simply because of how fragile it is and how I have damaged mine learning how to get out of it. My previous experience is with 5 different Nike Dri-fit shirts, all of which have been flawless in the durability department, but to not wick as well as the Phasic SL material. Now that I wrote this, I suppose I have made enough mistakes with the first one, that the second one will last longer, thus justifying the cost. If you learn from my mistakes, you should find it to be of good value.
Date published: 2012-09-02
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