Compare Maximum number of 4 items selected Autolite Iridium XP Spark Plug - XP64 Part #: XP64 Line: ATO Autolite Iridium XP Spark Plug Limited Lifetime Warranty Seat: Gasket Thread Size: M14-1.25 Heat Range: 9 Hex Size (mm): 21mm Hex Size (in): 13/16 Inch Preset Gap (in): 0.044 Inch Preset Gap (mm): 1.12mm Thread Reach (in): 0.750 Inch Center Electrode Core Material: Nickel Center Electrode Tip Material: Iridium Approximate Resistor Value (Ohm): 4000 Ohm Insulator Height (mm): 56.5mm Insulator Height (in): 2.223 Inch Ground Electrode Tip Material: Platinum Thread Reach (mm): 19.05mm Metallurgy: Iridium/Platinum Show More Show Less