... Phosphated, Nitrided,Chrome plated 3.ISO9002, QS9000, TS16949 engine piston ring set OEM manufacturer 1.Dia from 90mm--- ... years. DWIT products:Piston ring, piston, engine bearing, cylinder liner, liner kit, engine valve, valve seat and guide, thrust ... Korean & Japanese etc.Caterpillar, Cummins, Perkins, Komatsu, Mitsubishi, Nissan, Hino, Isuzu, Toyota, Daewoo, Hyundai, Kia, Volvo, Benz, MAN, DAF ...