6-New top quality OEM Holley  vacuum diaphragm housing lid screws for 1967-1969 Chevy Corvette 427 Tri Power carburetors and 1969-1971 Mopar, Dodge, Plymouth 340, 383, and 440 Six Pack carburetors, and Holley 3 barrel carbs. a must have for a proper restoration! see our store listings for Holley rebuild kits, and a huge selection of Holley carburetor parts.