Mopar performance reverse flange with the fins milled off. They did not fit with baffles over T&D rockers On the Indy heads I bought a fabricated set with no holes . Had my son weld 1/4 inch flanges on them that Bruce lazor cut. The thin flanges are not strong enough. You can see things are tight. I had to fit the push rods to the new flanges. Not much flange left. The way they were they did not seal.