1.Different Treatment: Phosphated, Nitrided, Chrome plated. 2.Quality certificates:ISO/TS16949:2009 3.Min quality:1000sets piston ring for perkins 1.piston ring for perkins 98.48mm 2.15years experience 3.3000000 pcs/month auto water pump piston ring for perkins1)perkins 98.48mm OEM NO.: 411580412)perkins 98.48mm OEM NO.:411580293)material:nodular iron,cast iron,steel,alloy,and etc(we can do as ...