Patented and engineered with heavyweight pads for rugged climbing. Medium weight padding at the shin prevents “boot bang.” 100% worsted wool at the toe offers maximum warmth. THOR-LON yarn, invented by THOR-Lo, gives Thorlos socks greater durability and softness found in no other socks. Made of 60% Worsted Wool, 2% Spandex, 27% THOR-LON Acrylic, and 11% Stretch Nylon. CONSUMER BENEFITS Helps prevent blisters Reduces destructive shear forces Optimal wicking to keep feet drier and healthier .Reduces pressure points Durability… longer lasting for a greater value Men's and Women's sizes available.