Up for auction is this pair of Pro Fab (Pro Fabrication) of super lightweight and top quality mufflers/resonators. 2.5 inlet/outlet, 4.5" diameter, 17" overall length. They are almost identical to Burns mufflers and cost a little bit less! These weigh less than 3.5 pounds each and are perfect for a racing application. Fiberglass filling.
Never been installed or used. More info here: https://profabrication.com/2-5-x-4-5-x-17-muffler/