Genuine OEM Audi Rear Bumper Diffuser, part number 8T0807521G01C. This aerodynamic component is integrated into the rear bumper to manage airflow underneath the vehicle, contributing to stability and performance. Finished in black (01C), it provides a factory-correct aesthetic. Using genuine OEM diffusers ensures precise fitment, optimal aerodynamic function, and durable material quality, maintaining the vehicle's intended design and performance characteristics.