This Heavy-Duty Impact Socket is Designed with More Than Two Times the Standard Socket Mass to Direct More Energy to Removing the Bolt. Can be used on Honda engines that use a 17mm Hex pulley damper bolt or other 17mm applications. Made with heat-treated, impact quality alloy steel. Use with 1/2\" drive. OD at the working end of the tool: 1.312 (1 - 5/16 inch)