NGK IZFR6K-11 vs IZFR6K-11S

[jazznewbie]

Hi guys,

I bought 4 NGK IZFR6K-11 spark plugs for my FD1. I have just realised the recommended spark plugs has a "S" at the end. Can I still use them or I have to get the one with the "S" at the end.

Cheers..

[EKVTIR-T]

the S means "special gasket" as in the crush washer must be slightly different to seal better

the plug specs are same
They feature a triple gasket sealing process that virtually eliminates gas leakage past the shell.