... 3.surface: galvanized 4.over ten years supplier Locking fasteners from hardware factory Material:stainless steel,steel,iron ... Hot Deep Galvanize(H. D. G. ) etc.Heat TreatmentTempering,Hardening,Spheroidizing,Stress Relieving.StandardISO,GB,DIN,JIS,ANSI ... ,BSWManufacture ProcessHeading/washer assembly/Threading/Secondary machine/heat treatment/plating/Anti-slipping/Baking/QA/Package/ShippingSample ...