Designed for runners, PhD Run Light Elite Low-Cut Socks feature targeted cushioning for impact protection on the ball and heel of the foot, where runners need it most. Mesh ventilation zones, a seamless toe, and 4 Degree elite fit system boost comfort and performance. Light elite cushioning designed specifically for runners: Provides maximum impact protection with targeted cushioning on the ball and heel of the foot. Overall height: 2.25 in. Blend of merino wool, nylon, and elastane. SmartWool delivers soft, itch-free comfort, even foot temperature, moisture management, and odor control. 4 Degree elite fit system uses two elastics for greater stretch and recovery to keep the sock in place and improve fit. Fit bands wrap and support the foot for more comfort, faster flex and recovery. ReliaWool technology in high-impact areas provides longer-lasting protection to keep feet comfortable. Mesh ventilation zones designed specifically for male runners provide optimal temperature regulation and moisture management. Virtually seamless toe. 200-needle construction provides highest-knit density, while maintaining ultralight weight. Knit in the USA of imported yarn. Machine wash warm, inside out, gentle cycle; tumble dry low or lay flat.