This is a set of 1" single hex deep impact sockets for everyday use either by mechanics technicians or engineering works and heavy use on rail yards etc. Manufactured from Chrome Vanadium Steel with a blackened finish for maximum durability. Specifications: 12 Piece deep socket set. Sizes: 24 26 27 29 30 32 33 34 35 36 38 41mm. 1 Inch dr. Length: 85mm. Professional quality. Chrome Vanadium Hardened Steel HRC42-45. Single hex. Deep impact.