SmartWool Women's PhD Cycle Ultra Light Micro Socks (Black) Medium 54% Merino Wool, 42% Nylon, 4% Elastane Knit in USA Built for Performance in the Highest Degree, Uses two elastics for greater stretch and recovery to keep the sock in place, Patented ReliaWool technology in high impact areas provides superior durability, Non-cushioned for maximum performance in close-fitting cycling shoes. Strategically placed mesh ventilation zones provide ventilation for temperature and moisture management. Virtually seamless toe Sock Height: Micro, 1.5" overall height Style: SW0SW076