Kelly Medium Elite Socks - RIBBED CONSTRUCTION STRETCH NYLON ATHLETIC SOCKS 100% STRETCH NYLON RECIPROCATED HEEL AND TOE CONSTRUCTION 5X1 RIB LEG CONSTRUCTION 1X1 RIB TOP CONSTRUCTION MADE IN THE USA SMALL (YOUTH SHOE SIZE OF 12-4, LADIES SHOE SIZE OF 4-5), MEDIUM (SOCK SIZE MEDIUM, LADIES SHOE SIZE 5-10, MENS SHOE SIZE 4 5-8 5) AND LARGE (SOCK SIZE LARGE, LADIES SHOE SIZE 11-12, MENS SHOE SIZE 9-12 5)