Replacement exhaust manifold includes A.I.R. holes and plugs. Can be used for 1957 283 Corvette right side, 1966-1971 327/350 Corvette right side and both LH and RH side on 1972-1980 Corvettes. Functionally correct but not cosmetically identical to OE or reproduction Corvette exhaust manifolds. Does not include an internal choke tube.