Carbon Fiber Rear Diffuser - Audi B9 S5 SportbackEnhance Your Audi B9 S5 Sportback with the Carbon Fiber Rear Diffuser from Ausen Performance Upgrade your Audi B9 S5 Sportback with the premium carbon fiber rear diffuser from Ausen Performance. Engineered to improve aerodynamics and add a bold, aggressive look, this diffuser enhances both the performance and appearance of your vehicle. Crafted from high quality carbon fiber, the Audi B9 S5 carbon fiber rear diffuser reduces drag, improves airflow,