4 New NGK Iridium IX Spark Plugs DPR7EIX-9 # 7803, Iridium IX Plug, 12mm Thread Size, 19mm (3/4") Reach, 11/16" (18mm) Hex Size, Gasket Seat, Resistor, Stud Terminal Threads, Projected Tip, Fine Wire (0.6mm) Iridium Center Electrode, Tapered Cut Ground Electrode, .035" (0.9mm) Gap, Heat Range 7. NOTE: Does not Include Terminal Nut