The Darn Tough Light Hiker Micro Crew Taupe features a new smooth ribbing upper that stays put forever, and extended cushion over the Achilles. The men's 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 micro crew height sock is light and strong with a versatile construction. It comprises of 54% nylon, 43% merino wool and 3% lycra?Â« spandex.