Suitable for mechanical use, best chrome vanadium steel, doubly nickel coated & chrome coated. A 4 piece socket set with hexagonal direct drive made from quality chrome vanadium steel. Fits into any chuck & therefore offers the possibility to quickly use the sockets in your drill or re-chargeable screwdriver. Contents: 5.5, 8, 10, 13mm – safely stored in a bit holder. Thanks to the high quality surface coating the socket set offers highest rust protection. The additional knurl allows a quick-screw by h&.