NGK Laser Iridium spark plugs offer the best combination of performance and longevity. Engineered specifically for OE applications, Laser Iridium spark plugs are tested to the highest standards to ensure quality and durability. Iridium tipped center electrode provides durability six times harder than platinum. NGKs high grade pure alumina ceramic and 98% pure copper core prevents the spark plug from overheating while providing reliable starts. Most Laser Iridium spark plugs feature a platinum pad on the ground electrode for even wear in distributor ignition systems. Iridium Alloy Center Electrode: Iridium is 6x denser than platinum and highly resistant to melting Solid Copper Core: 98% pure copper core provides superior heat dissipation and conductivity Trivalent Metal Plating:Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal Fine Wire Iridium Heat Range: 8Resistance: 5000 OhmThread: M10 x 1.0mmHex: 14mmGap: 1.0mmSold individually