This American Thunder cat-back exhaust system is for 2004-2007 Dodge Durango and 2007 Chrysler Aspen SUV's with the 4.7L or 5.7L Hemi engine. Features include a stainless steel 70 Series Big Block II performance muffler for a mild to moderate interior sound, with a deep powerful sound outside without hindering performance. The mandrel-bent 2.50 in. stainless tailpipes exit side by side out the back and are finished off with a pair of polished 3.00 in. stainless steel with the Flowmaster logo embossed in the tips. Like all Flowmaster systems, the benefits include improved throttle response, power and mileage. Designed for an easy fit, these systems include all necessary parts and hardware for easy installation. The system is covered by our Limited Lifetime Warranty.