Spark Plug Application Marine Hex Size 45/64 in Thread Size 0.472 in Thread Reach 0.75 in Ground Electrode Quantity 1 Ground Electrode Tip Design Standard Gap Size 0.035 in Resistor Plug Yes Hex Size - Metric 18 mm Thread Reach - Metric 19.05 mm Insulator Material Ceramic Manufacturer Heat Range 6 Seat Type Flat Center Electrode Diameter 0.098 in Ground Electrode Material Nickel Core Center Electrode Material Nickel Compatible Vehicle Make Yamaha Package Quantity 10