Champion Iridium Spark Plug - 9810 Part #: 9810 Line: CHP Champion Iridium Spark Plug 5 Year Limited Warranty Seat: Flat Thread Size: M14 Heat Range: 8 Hex Size (mm): 15mm Hex Size (in): 5/8 Inch Preset Gap (in): 0.028 To 0.700 Inch Thread Reach (in): 0.750 Inch Resistor Plug: Yes Center Electrode Tip Material: Iridium Insulator Height (in): 0.300 Inch Ground Electrode Tip Material: Iridium-Platinum Show More Show Less