Genuine OEM BMW NOx Sensor, part number 13628580410. This sensor measures nitrogen oxide levels in the exhaust gas, playing a critical role in the vehicle's emissions control system. It is typically located in the exhaust stream before or after the catalytic converter. The sensor is made of durable materials designed to withstand high exhaust temperatures. Genuine OEM sensors ensure precise readings and proper integration with the vehicle's engine management system for optimal performance and emissions compliance.