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  • Merino wool regulates body temperature, breathes well and naturally resists odors
  • Smooth flatlock seams and and a wide, fabric covered waistband minimize chafing
  • Core Spun technology features a nylon core for added durability, while keeping the comfort of soft merino wool next to your skin
  • Fully functional fly
  • Slim fit; mid rise


View all Smartwool Men's Long Underwear Bottoms

REI membership


Best Use Hiking
Fabric 87% merino wool/13% nylon
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Lightweight
Inseam (in.) 31
Gender Men's

Size chart

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got a problem here in listing sizes, at least on my browser, but why is it listing shirt measurements when it is clearly long leg wear? the real question is length of the underwear legs for small, medium and large, and do you have any tall sizes?

Asked by: Unomonoloco
We do not carry this pair of long underwear in tall sizes. The inseam is 31 inches. The size chart shown is for all SmartWool clothing, not just this pair of long underwear, so it does list shirt sizing as well.
Answered by: REIservice
Date published: 2017-01-06

Being mostly wool, can they be thrown into the regular wash, or are they hand wash only? Do they shrink?

Asked by: Papa
These bottoms can be machine washed. Low heat or hung to dry.
Answered by: REIservice
Date published: 2017-04-03
  • y_2017, m_6, d_25, h_2CST
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