Super 40 - 2.50 Offset In / 2.50 Offset Out - Aggressive Sound; The Super 40® features Flowmaster s Delta Flow technology. It s larger case profile provides the best of both worlds of performance and sound. 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 aluminized steel and fully MIG welded for maximum durability.;