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 propertiesCorrugated ribs prevent flashoverPure alumina silicate ceramic insulator, provides superior strength and better heat transferCopper core aids in heat removalTriple seals prevent leakageShellThread Diameter14mmThread Pitch1.25mmSeat TypeGasketReach19mm (3/4")Hex Size5/8" (16mm)Terminal TypeSolidOverall HeightISOGap 0.8mmCenter ElectrodeMaterialIridiumTypeFine WireSize0.6mmProjectionProjectedGround ElectrodeMaterialNickelTypeStandardShapeTaper CutQuantity1SpecificationsResistorYesResistor Value5k OhmHeat Range 8Torque SpecsCast Iron: 18-25.3 lb. ft. Aluminum: 18-21.6 lb. ft.SKU: NGK 3764Suits:S14/15 Silvia/200SX - SR20DETS13 Silvia/180SX - SR20DETR33/34 Skyline RB25DETR34 Skyline RB25DET NeoWRX & STI EJ20 V1-6WRX & STI EJ20 V7-9Toyota Supra 2JZGTEToyota Celica/MR2 3SGTE