Silverado/Sierra 4 Inch Cat Back Exhaust System Single Side Exit 20-20 Silverado/Sierra 2500/3500 HD 6.6L V8 MBRPEnhance your Chevrolet GMC 2500 3500 HD with added power and a better sound by installing the MBRP S5093AL exhaust system. This cat back exhaust is made from 4 inch smooth aluminized steel mandrel bent tubing, which enables enhanced flow, boosting your truck's performance the S5093AL's design saw improvements of up to 8 horsepower and 8 ft lbs of torque. Don't forget the additional advantage of the timeless MBRP exhaust sound. The S5093AL produces a