... service metal case : Product Type metal case Materialsteel sheet, Al sheetMachining typestamping, punching, bending, welding, powder coating etc..Surface finishPolishing, and Chrome plating, zinc plating ... steel,aluminum,cold rolled steel with various plated;3)Surface treatment:kinds of plating(Zinc,Nikel,Chrome,Tin,Ag);Painting,Powder,Anodizing ...