Features of the Smartwool Women's PhD Run Light Elite Low Cut Sock Indestructawool Technology Features a wool-based, patent-pending yarn and construction method for exceptional durability and comfort 4 Degree elite Fit system Uses two elastics for greater stretch and recovery. Narrower profile provides perfect women's-specific run Fit Mesh ventilation zones designed specifically for female runners provide optimum temperature regulation and moisture management Virtually Seamless toe Made in USA