This Carburetor Bushing Kit reduces the 1/2 inch throttle shaft hole to 1/4 inch i.d., (inner diameter) which makes for easy throttle linkage attachment, or can be used to replace the stock rubber unit. Machined from cold roll steel, then bright zinc plated, the two piece bushing measures 9/16 inch wide when installed and fits most 4-barrel carburetors with 1/2 inch throttle linkage hole. Application: All GM (General Motors) and most Holley Carburetors with 1/2 inch diameter throttle hole.