NOx sensor for a device that is used to measure nitrogen oxygen (NOx) concentration in vehicle exhaust and other emission sources.

The NOx sensor is important because nitrogen oxides are harmful to the environment and human health. Their reduction is crucial for improving air quality and reducing the emission of harmful compounds.

The NOx sensor works on the principle of electrochemical detection of nitrogen oxides. As the exhaust gas flows through the sensor, the nitrogen oxides react with the electrodes inside the sensor, generating an electrical signal.

The NOx sensor is usually located in the car's exhaust system, either in front of the catalytic converter or in the catalytic converter.