NGK Yellow Box Spark Plug Part Number: BU8H Part Number: 6431, Trade No: BU8H Manufacturer: NGK Thread Length : 12.7mm Outer thread : 14mm Hex Nut Size : 20.8 mm Spark projection : 0.3mm Connector Type : Fixed SAE Spec : Nickle centre electrode Spec : Surface Spark Spec : no interference suppression Gasket Type Seat Quantity: 1 As the main source of power in any petrol engine, a spark plug performs an essential function: It is responsible for igniting the air-fuel mixture in the combustion chamber of petrol engines. This combustion process creates power, ultimately setting the vehicle in motion. NGK Spark Plugs are high quality and have a: - Unique design to guarantee the best possible performance - Wide range of different heat ratings for high thermal endy