Champion Plug Number QA8HCX Spark Plug - 810ECO Part #: 810ECO Line: CHP Champion Plug Number QA8HCX Spark Plug 1 Year Limited Warranty Thread Size: M12 Heat Range: 8 Hex Size (in): 5/8 Inch Preset Gap (in): 0.035 Inch Resistor Plug: Yes Center Electrode Tip Material: Nickel Insulator Height (in): 0.030 Inch Ground Electrode Tip Material: Nickel Service Number: QA8HCX Metallurgy: Copper Show More Show Less