Compare Maximum number of 4 items selected NGK Iridium Plug Number TR55IX Spark Plug - 7164 Part #: 7164 Line: NGK NGK Iridium Plug Number TR55IX Spark Plug 1 Year Limited Warranty Seat: Tapered Thread Size: M14-1.25 Heat Range: 5 Hex Size (mm): 16mm Hex Size (in): 5/8 Inch Preset Gap (in): 0.060 Inch Preset Gap (mm): 1.5mm Thread Reach (in): 0.689 Inch Center Electrode Core Material: Copper Center Electrode Tip Material: Iridium Approximate Resistor Value (Ohm): 5000 Ohm Insulator Height (mm): 52.5mm Insulator Height (in): 2.070 Inch Thread Reach (mm): 17.5mm Service Number: TR55IX Metallurgy: Iridium Show More Show Less