Features 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; Specifications Thread Size: 12 mm; Material: Nickel; Dimension: 0.12″ H x 0.79″ W x 0.88″ L; Weight: 0.12 lbs; .