NGK Standard Series spark plugs are designed for stock replacement applications. These plugs have a hotter spark, which means better combustion and that improves performance, while producing less harmful emissions. Shorty Spark Plug: No. Resistor: No. Manufacturer Heat Range: 6. Electrode Tip Material: Nickel alloy. Electrode Core Material: Copper. Insulator Type: Non-projected. Spark Plug Thread Size: 14mm. Spark Plug Reach: 0.437 in. Spark Plug Seat Style: Gasket. Wrench Diameter: 13/16 in. Ground Strap Quantity: One.