NGK IX Iridium Series plugs were designed specifically for the performance enthusiast. Fine wire center electrode ensures high durability and a consistently stable spark Iridium alloy has an extremely high melting point, perfect for today's high-tech, high performance engines Trivalent metal plating provides superior anti-corrosion and anti-seizing properties Corrugated ribs prevent flashover Pure alumina silicate ceramic insulator, provides superior strength and better heat transfer Copper core aids in heat removal Triple seals prevent leakage MPN: BPR8EIX Specifications Warranty 1 Year Torque Specs Cast Iron: 18-25.3 lb. ft. Aluminum: 18-21.6 lb. ft. Brand NGK Heat Range 8 Longevity 50k Miles Resistor Yes Shell Thread Size 14mm Thread Pitch 1.25mm Seat Type Gasket Resistor Value 5K Ohm Reach 19mm (3/4") Hex Size 13/16" (21mm) Terminal Type Removable Nut Overall Height JIS Gap .031" (0.8mm) Center Electrode Material Iridium Type Fine Wire Size 0.6mm Projection Projected Ground Electrode Material Nickel Type Standard Shape Taper Cut Quantity 1 Fitment