Bosch Super Class Platinum+4 Spark Plug has 4 ground electrodes and the most platinum in all of Bosch's platinum series. These plugs deliver top fuel economy and maximum engine power while having longest service life.
Platinum+4 plugs features the surface air gap firing technology that delivers the most powerful spark for ultimate engine performance. These plugs also feature a fine wire platinum center electrode that is heat fused into the extended ceramic insulator to reduce the voltage necessary to jump the gap and as reduce quenching. These plugs are equipped with 4 Yttrium alloy ground electrodes that help reduce gap wear and oxidation - extending the service life of the spark plug.