Made from highly polished chrome vanadium steel to a professional standard for the skilled mechanic or engineer. With 1/2" drive. Can also be used with 19mm 22mm spanners with the hex drives on the top of the socket. The extractors are the concentric roller bearing type that won't damage the thread on the stud. They can used for stud removal and stud fitting with no damage to the thread. Contents: Sizes: 6, 8, 10 and 12mm Supplied in a blow moulded case for storage.