This Crossmember-Back American Thunder system is custom designed for high horsepower and large cubic inch engines in 1967-1969 Chevrolet Camaro and Pontiac Firebirds with a V8 engine. It's a true-dual exhaust system featuring all mandrel-bent 3.00-inch aluminized steel tubing with a built-in H-pipe crossover assembly flowing into a pair of large cased Super 40 Series performance mufflers for maximum power and a deep powerful aggressive exhaust note. The large 3.00-inch mandrel-bent tailpipes are custom bent to tuck up high above the rear end and exit with a slight turn down at the quarter panels behind the rear wheels. The system is constructed from aluminized steel and includes all necessary hardware and hangers for installation. Covered by our 3-year Limited Warranty.