The Men?s Classic Thermal Merino Bottoms from Smartwool have been updated for a better fit and functionality. The 100% responsibly sourced Merino wool fabric has an interlocking knit to improve breathability and thermoregulation, keeping you in maximum comfort throughout the day. The slim fit bottoms have a flatlock seam construction which is designed to reduce chafing and also has a fully functional fly and merino-lined elastic waistband. Smartwool Men's Classic Thermal Merino Bottom - Black | George Fisher