Compare Maximum number of 4 items selected Autolite Iridium XP Spark Plug - XP104 Part #: XP104 Line: ATO Autolite Iridium XP Spark Plug Limited Lifetime Warranty Seat: Tapered Thread Size: M14-1.25 Heat Range: 9 Hex Size (mm): 16mm Hex Size (in): 5/8 Inch Preset Gap (in): 0.050 Inch Preset Gap (mm): 1.27mm Thread Reach (in): 0.679 Inch Center Electrode Core Material: Nickel Center Electrode Tip Material: Iridium Approximate Resistor Value (Ohm): 4000 Ohm Insulator Height (mm): 51.5mm Insulator Height (in): 2.026 Inch Ground Electrode Tip Material: Platinum Thread Reach (mm): 17.25mm Metallurgy: Iridium/Platinum Show More Show Less