... steel , stainless steel , aluminum alloy , zinc alloy , brass , gray iron , nodular cast iron , ductile iron specified StandardASTM ... sand casting MachiningTurning , milling , drilling , grinding , threading , CNC machining, etc. FinishingSand blasting , polishing , plating , acid treatment , anodizing ... impact testing. CertificateISO9001:2000 Main productsCNC Machining Parts , Investment Castings