It is designed to work on single 4 barrel carburetors systems. It features a single bell crank design that is mounted on bearings for a flex free and smooth operation. This design allows the linkage to be tucked in tight against the carburetors for optimum hood scoop clearance. The linkage is made from 5/16” aluminum hex rod threaded 10-32” RH and LH for fine adjustment. Requires qty-1 aluminum threaded bungs to mount to your manifold top (sold separately) Comes with all hardware and instructions.