Developed from our Top Ten race muffler lineup for use on the street/strip, the Super 40® features Flowmaster's Delta Flow® technology. It's larger case profile provides the best of both worlds of performance and sound, especially on forced induction and high horsepower vehicles. The Super 40 has that deep powerful sound of the Original 40 series but with all the benefits of performance and low interior resonance from the Delta Flow® technology. Constructed of 16 gauge 409S stainless steel and fully MIG welded for maximum durability.