... C36000 ( C26800), C37700 ( HPb59), C38500( HPb58), C27200CuZn37), C28000(CuZn40) 4.Bronze: C51000, C52100, C54400, etc5.Iron: 1213, 12L14,12156.Aluminum ... .StandardISO,GB,DIN,JIS,ANSI,BSWManufacture ProcessHeading/washer assembly/Threading/Secondary machine/heat treatment/plating/Anti-slipping/Baking/QA/ ... Display Any questions, please feel free to contact us! self-tapping screw with many size&use