AWE Tuning Audi B7 S4 Touring Edition Exhaust - Polished Silver TipsWelcome to the finest catback exhaust for the B7 Audi S4 on the market. The AWE Touring Edition Exhaust for the B7 S4 is a direct bolt on catback system that not only transforms the rear end of the car with its menacing quad tips, but also turns heads with a deep muscluar bass note. Each cat back system features an H Pipe crossover tube at the front to maximize exhaust scavenging for maximum power, as well as to take a harsh edge off the exhaust