Hollow punch machining part: 1 Metal leather punch 2 Precision punch machining ... Surface treatment: zinc plated, power coated, chrome plated, hot-dip galvanized, etc or according to your drawings.5. ... fields, such as automobile, metallurgy, heavy-duty machinery and navigation. We are annually exporting more than ... punch set, Leather working, Punch and die, Metal punch, Machinery parts, Machining parts