... so on 2.Material :aluminum, mild steel, stainless steel, chrome steel, cold rolled sheet, bearing steel, brass, copper, bronze, chrome copper, mold steel , teflon ,PVC, bakelite, nylon, delrin ... treatment:hardening, carburizing, high frequency, anodizing, clear anodizing,black anodizing ,chrome plating, black oxide coating, nickel plating, zinc plating, nitriding, degreasing ...