The Spectre Carburetor Spacer is a universal spacer/adapter that has been designed for Holley, Edelbrock or AFB carburetors. Manufactured using high quality materials, the outer plate precision die cast aluminum with heat insulating phenolic material. It is 1 inch thick and comes with an open spacer insert and a 4 hole spacer insert to allow you to the option that works best for you. This Spectre carburetor spacer is designed to increase power by raising air/fuel velocity as it enters the intake manifold. This adapter kit includes the needed gaskets and hardware for a fast and easy installation. The Spectre Carburetor Spacer is a universal spacer/adapter that has been designed for Holley, Edelbrock or AFB carburetors. Includes an open spacer insert and 4 hole spacer insert.