The Darn Tough Solid Crew Lightweight Chestnut men's sock provides toughness with classy styling. The lightweight hiking sock features merino wool, fine gauge knitting, fast action wicking and true SeamlessT to offer an ultra smooth, invisible feel. The sock is guaranteed for life and is naturally antimicrobial. The crew height sock is built light, darn comfortable and super strong to provide a lightweight, sure fit. It comprises of 57% merino wool, 41% nylon and 2% lycra?Â« spandex.