The Holley 4500 Dominator is a large race-only carburetor in the modular series, first introduced in 1969. They range in size from 750 cfm up to 1250 cfm, and use a specific Dominator flange, with bolt centers at 5.375 X 5.375 inches.
Carburetor numbers are stamped on the front of the choke tower. How to find Holley carburetor list numbers