Do you want the most out of your car's exhaust system? Then our Thunderstorm Exhaust products are for you! We pride ourselves on taking our race tested exhaust technologies to the streets. Thunderstorm Exhaust Products offers this true high flow, larger diameter, free flowing cat-back exhaust system. These Thunderstorm cat-backs are made in America of T304 Stainless Steel and featuring patented sound cancellation technology. and mandrel bends. This technology tunes out annoying low frequencies that causes droning and replaces it with a crisp clean exhaust note.