Introduction of the hex socket: the hex is a standard size of 6.35 mm. One head is 2 hole two slot SDS shank, the other is hex socket. The 60mm black knurled models can handle greater torque, and the 60mm and 70mm silver models have no knurling. High quality material: chrome vanadium steel, integrally formed, durable, reliable quality. Chrome vanadium steel suitable for heavy-duty impact screwdrivers. Spring-loaded ball bearing on head holds sockets securely. Easy to use: The flexible shield protects the hand from injury when the inner shaft rotates. Use a drill bit to bend, twist and turn in a confined space. Product use: It can convert an electric hammer, impact drill and other original SDS connection method into an internal hexagonal connection method, so it can connect all kinds of drill heads. drills, countersinking tools, drill bits and other hex shank tools. Wide Application: Great for woodworking, carpentry, machinery and auto parts repair, etc. Nice gift for DIY enthusiasts.