SmartWool Men's PhD Snowboard Light Socks - Past Season 56% Merino Wool, 43% Nylon, 1% Elastane Light Cushion: Light cushioned sole, shin and calf for impact absorption. Mesh Venting: Men's-specific mesh ventilation zones provide additional breathability and moisture management. PhD = Built for Performance in the Highest Degree. 4 Degree Elite Fit System: Uses two elastics for greater stretch and recovery to keep the sock in place. ReliaWool: Patented ReliaWool technology in high impact areas provides superior durability. Flat knit durable toe seam Sock Height: Over the Calf: 14" overall height Style: SW0SW031 - Knit in USA