... steel screws, the head is the hexagon, the teeth are machine wire teeth, 1,Products DetailesMaterial1.Stainless Steel:SS201, SS303, SS304 ... . ) etc.Heat TreatmentTempering,Hardening,Spheroidizing,Stress Relieving.StandardISO,GB,DIN,JIS,ANSI,BSWManufacture ProcessHeading/washer assembly/Threading/Secondary machine/heat treatment/plating ...