... treatment:Phosphated, Nitrided etc. 3.ISO9002,QS9000,TS16949 Piston Ringpiston ring for Isuzu 4JB1:1.piston ring material :nodular iron, cast iron, steel ... fuel consumption4)long working life4.Our piston ring model as follows:CommodityPart NumberCummins piston ring6BT,6CT,NT855,NH220,NH250,N14,V265,V300,VT6 ...