Champion Iridium Plug Number RER8WYPB4 Spark Plug - 9408 Part #: 9408 Line: CHP Champion Iridium Plug Number RER8WYPB4 Spark Plug 2 Year LIMITED WARRANTY Seat: Gasket Heat Range: 8 Hex Size (mm): 16mm Hex Size (in): 5/8 Inch Preset Gap (in): 0.041 Inch Preset Gap (mm): 1.05mm Thread Reach (in): 1 Inch Center Electrode Tip Material: Iridium Insulator Height (in): 0.080 Inch Ground Electrode Tip Material: Platinum Service Number: RER8WYPB4 Metallurgy: Iridium/Platinum Show More Show Less