The Super 40 Muffler was developed from our Top Ten race muffler lineup for use on the street and strip. Utilizing Delta Flow Technology, this muffler gives the best performance to higher horsepower vehicles. The Super 40 features a black, oversize case, which keeps the resonance down while the deep outside tone says it’s a Flowmaster! Constructed of 16-gauge aluminized steel and fully MIG-welded for maximum durability. 5" Thick x 10" Wide x 13.5" Long with inlet/outlet sizes from 2.25" up to 3".