Genuine OEM Audi Rear Brake Pad Wear Sensor, part number 7L0907637. This electrical sensor is installed on the rear brake pads, continuously monitoring their thickness. When the pads wear down to a critical level, the sensor triggers a warning light on the dashboard, alerting the driver that replacement is needed. This ensures timely maintenance and braking safety. Weighing approximately 0.03 kg, this sensor features precise electrical calibration. Choosing a genuine OEM sensor guarantees accurate readings, proper electrical integration, and reliable performance for critical safety systems.