For the person who wants a subtle custom appearance with all the benefits that a Flowmaster Cat-back exhaust system provides. S.O.R. (Single Out Rear) systems are the perfect choice. This American Thunder system delivers a moderate interior and exterior tone and is suited to the enthusiast who wants their performance to be heard. 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.