... tapping screws,slotted flat head tapping screws and so on.There is all kinds of size of our products.And our ... trade with us,please contact with me. This is the information of the product: 1.Color plating:environmental nickel plating 2. ... treatment: galvanized steel, nickel plating, chrome plating, phosphating, polishing, the surface hardening, carburizing and quenching, sand blast, oxidation. 4.Strong ...