Genuine OEM Audi Brake Pad Wear Sensor, part number 4H0615121J. This sensor is designed to monitor the wear level of the brake pads, providing a critical signal when replacement is necessary. It is installed in the front wheel assembly. With a length of approximately 31.4 cm, it ensures accurate and reliable wear detection. Choosing a genuine OEM sensor guarantees precise fitment, electrical integrity, and long-term reliability, which are vital for the vehicle's braking system.