Expert Quality, manufactured from chrome vanadium steel hardened and tempered with a micro satin finish. Each socket has a knurled ring for extra grip. Supplied on a metal socket rail for secure storage. Display packed. Contents: 13 x Sockets: 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, 13/16, 7/18, 15/16, 1, 1.1/16, 1.1/8" Manufactured and tested generally in accordance with DIN3122 and ISO3315 Specifications