... Treatment: Phosphated, Nitrided,Chrome plated 3.ISO9002, QS9000, TS16949 engine piston ring set OEM manufacturer 1.Dia from 90mm---139mm2 ... .Engine Type: W04D,EH700, M10U, EK100, EF750, F17C, EF500-550, KBC ... 45 years. DWIT products:Piston ring, piston, engine bearing, cylinder liner, liner kit, engine valve, valve seat and guide, thrust washer, ...