Smartwool PhD Outdoor Ultra Light Crew Socks Ideal for warm weather or those that want minimal cushioning, this ultra lightweight sock features the power of Merino for maximum breathability, moisture management and temperature regulation. Featuring Indestructawool technology for ultimate durability and the 4 Degree elite fit system to keep the sock in place. The crew height fits well in mid-height boots and helps protect against trail debris. Indestructawool technology features a patent-pending construction method for exceptional durability and comfort. Mesh ventilation zones provide optimum moisture management and maximum breathability. Minimal cushioning for maximum performance in close-fitting shoes. Features: Sock Height: Crew 8.5" overall height Virtually Seamless toe Minimal cushioning for mazimum performance in close fitting shoes Made in USA of Imported Yarn: 49% Merino Wool, 46% Nylon, 5% Elastane