... are the professional manufacturer(factory) that produce all kinds of engine valves,we have motorcycle valves, diesel engine valves ,auto engine valves and ... IS SUH1(40Cr) ; EXHAUST VALVE IS SUH3(4Cr9Si2).Engine valves are suitable for TOYOTA,AUDI,BESFORD,BMW,CATERILLAR,CUMMINS ... plating , surfacing nitration treatment.Of course , we can produce engine valves according to your samples .MARK IN / EX GUNES ...