NGK's Laser Iridium Spark Plugs provide superior ignitability and long service life. Fine wire iridium tipped center electrode and fine wire platinum tipped ground electrode ensure slow wear rate for stable idle, superior anti-fouling, improved fuel efficiency, and lower emissions. Tivalent metal plating provides superior anti-corrosion and anti-seizing properties. Corrugated ribs prevent flash-over. Pure alumina silicate ceramic insulator provides strength and better heat transfer, while copper core aids in heat removal. Triple seals prevent leakage. Iridium center electrode and platinum ground electrode. 14mm thread size. 1.25mm thread pitch.