... steel 3.Machining,milling,grinded,polished. 4.Tolerance:+/_0.01mm Milling parts & CNC machining parts 1,Material: Brass, ... Carbon steel, Aluminium etc 2,Machining process: CNC turning, Milling, Drilling, CNC lathe etc 3,Surface treatment: Plating with Zinc, ... sliver, Nickel, Chrome, gold, Polishing, 4,Anodizing, Oil, Painted ...