The Kincrome socket sets are perfect for any professional application. Manufactured from chrome vanadium steel, these sockets have been hardened, tempered, chrome plated, and polished for corrosion protection. All are protected by a sturdy machined tin. Kincrome Sockets and Accessories are Manufactured from Chrome Vanadium Steel (Cr-V) and Chrome Plated to Prevent Corrosion Durable 72 Teeth Quick Release Ratchets - The socket is locked securely while in use but can be removed quickly and easily even with greasy or oily fingers Supplied in a tin with an insert for storage. Specifications 12 1/4 Drive Metric Sockets: 4, 4.5, 5, 5.5, 6, 7, 8, 9, 10, 11, 12, 13mm 14 1/2 Drive Metric Sockets: 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22mm 10 Accessories Ratchet Handle 1/4 Drive Ratchet Handle 1/2 Drive Universal Joint 1/4 Drive Universal Joint 1/2 Drive Extension Bar 1/4 Drive 50mm Extension Bar 1/4 Drive 150mm Extension Bar 1/2 Drive 75mm Extension Bar 1/2 Drive 125mm Spark Plug Socket 1/2 Drive 16mm (5/8) Spark Plug Socket 1/2 Drive 21mm (13/16)