... Stainless steel, Aluminum alloy,Surface Treatment: Chrome plating, Silver plating, Zinc plating, Nickel plating, Tin-plating, Passivate, Oxidation, Phosphorization, Radiant Plated, ... hexagon, Hexagon washer head, Hexagon socket button head and etc. 3. by type of drive inserts Phillilps, ... equipments, projects, constructions, Bridges, traffic appliances and so on.We're ready to provide you qualified ...