... Hardness:45-50HRC 3.OEM welcomed 4.Processing: Forging,Lathe,Hobbing,Quenching,Broach keyway industrial sprocket,plate sprocket Material: C45, A3Hardend ... Teethprocessing: forging hobbing, quenching. CNC machineManufacture strictly in according to ISO, DIN,ANSI ... ,28B9-76,32B9-76 PackingPlastic bag+plywood case/Pallet 06B gear sprocket