AVO Turboworld Exhausts are constructed from the highest quality TIG-welded stainless steel. We take a lot of care to make our mufflers by hand, using stainless steel flanges as well to ensure longevity. Our mufflers are not packed with cheap fiberglass filling like many other makers, instead we use stainless steel mesh, which we have found to last best. Sound is also very important to us, we donít feel that louder is better. A muffler must produce a mellow, deep note that encourages you to drive and to meet all local noise level standards.