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 ensures slow wear rate providing stable idle, superior anti fouling, improved fuel efficiency and lower emissions.14mm thread size, 1.25mm thread pitch shell0.6mm fine wire iridium extended projection centre electrodeTaper-cut standard platinum ground electrodeTrivalent 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 leakage