Vibrant Performance race mufflers are designed to comply with the rules and avoid performance loss tracks All over North America are requiring sound reduction equipment. Vibrant race mufflers are constructed out of T304 stainless to be lightweight, compact, and durable. They feature their unrestricted "true straight through" perforated core that cuts the noise without cutting your performance are you looking to shave even more weight? of course you are vibrant aluminum race mufflers are crafted from T6061 aluminum with tig-welded seams and the same unrestricted, flow-through design as their stainless steel race mufflers. More flow equals more power where do you start to fabricate your custom race exhaust? Vibrant Performance race mufflers are a great start