1) stainless steel ball by deep drawing, 2) 304 material with mirror polished outside ... to customer's drawing with the format like .dwg/.igs/.stp/.pdfMaterialStainless Steel, Mild Steel, Aluminum, Galvanized steel, Spring Steel, Brass, Bronze, ... yellow passivation, gold passivation, galvanizing, satin, etc.Processing MethodDeep drawing , stamping , punching, bending, CNC spinning, CNC machining, ...