NGK Copper Plug Number CM-6 Spark Plug - 5812 Part #: 5812 Line: NGK NGK Copper Plug Number CM-6 Spark Plug 1 Year Limited Warranty Seat: Gasket Thread Size: M10-1.0 Heat Range: 6 Hex Size (mm): 14mm Hex Size (in): 5/8 Inch Preset Gap (in): 0.016 Inch Preset Gap (mm): 0.4mm Thread Reach (in): 0.339 Inch Resistor Plug: No Center Electrode Core Material: Copper Center Electrode Tip Material: Nickel Insulator Height (mm): 24.9mm Insulator Height (in): 0.980 Inch Ground Electrode Tip Material: Nickel Thread Reach (mm): 8.6mm Service Number: CM-6 Metallurgy: Copper Show More Show Less