Description NGK Spark Plugs are designed to operate over a much wider heat range than ordinary plugs. They resist carbon buildup and pre-ignition. Each features high alumina ceramics for better heat transfer and electrical insulation. A patented triple gasket sealing process eliminates the possibility of combustion gas leakage, and a longer insulator nose prevents fouling and misfiring. A solid copper core and its nickel tipped electrode provide a longer plus life.