CUMMINS Parts Nitrogen Oxygen sensor 5WK9 6674A 2871978 made of high-quality material for long-lasting durability. Nitrogen Oxide sensor as one of the important members of SCR system,are composed of sensor probe and Electronic control unit.They are connected by a wire harness to measure the concentration of nirtrogen oxides in tailgas and the concetration of oxygen. The nitrogen oxide sensor provides the basis for SCR injection quantity, in order to reduce the Nox emission. Nitrogen Oxygen Sensor in practical application, the probe is installed in the automobile exhaust pipe, and the ceramic chip in the sensor will feed back the concentration value of the exhaust gas to the electronic control unit in the form of voltage. Quality Guarantee :1 year, and strictly in accordance with the standard quality inspection The products are 100% new and carefully packed.