Genuine OEM BMW Lambda Probe Sensor, part number 13627801158. This sensor measures the oxygen content in the exhaust gases, providing crucial data to the engine control unit for optimizing fuel combustion and emissions. It is typically located in the exhaust system before or after the catalytic converter. The sensor is constructed with durable materials to withstand high exhaust temperatures. Genuine OEM sensors are precisely calibrated to ensure accurate readings, which is vital for maintaining engine efficiency and meeting emissions standards.