Spark PlugMaintaining your car at suggested service intervals will result in a better performance and improved fuel economy, which is why we suggest changing your spark plugs at the manufacturers suggested service intervals and be sure to check their condition for any warning signs of failure. If your vehicle isn't operating at peak performance it may be time to replace your spark plugs. Brand: TOPRANProduct Nr: 111 9791 earthed electrodereplace as a complete setno mixed installation of different manufacturers permitted-Sold Individually Compatible with OEM numbers;Audi - 101 905 611AAudi - 101 905 631ABMW - 0 032 134BMW - 0 032 135BMW - 2 158 252BMW - 1212 0 032 134BMW - 1212 0 032 135BMW - 1212 2 158 252NGK - PFR6X-11NGK - PFR6U11GNGK - 5874NGK - 5757