Designed to be free flowing with low back pressure!Bully Dog Technologies' Rapid Flow Exhaust Systems are designed and built with absolute minimal degree angles on bends. This creates a free flowing, low backpressure system that allows the turbo to move air more freely, reducing exhaust temperatures by as much as 200 degrees which results in more horsepower and torque. Dyno results have shown a significant gain in horsepower by simply switching from stock to a Rapid Flow System. Available in 4'' & 5'' 16-gauge aluminized or T304 stainless steel. Also available in single or dual outlets.