Denso Copper Plug Number T16EPR-U15 Spark Plug - 5023 Part #: 5023 Line: DEN Denso Copper Plug Number T16EPR-U15 Spark Plug 1 Year Limited Warranty Seat: Tapered Thread Size: M14 Heat Range: 16 Hex Size (mm): 16mm Center Electrode Core Material: Copper Center Electrode Tip Material: Nickel Approximate Resistor Value (Ohm): 5000 Ohm Service Number: T16EPR-U15 Metallurgy: Copper Show More Show Less