philip head machining screw 1/ micro machining 2/ high quality steel alloy ... head machining screwsMaterialStainless steel, Carbon Steel, copper, ironMachining method Screw machiningSurface finishChrome plating, zinc plating, blackening, Nickel plating, Electrophoresis ... parts by express, 3~5 days door to door service.Application Surgical instruments, Optical products, LED flash lights, mobile ...