Oversize brass ferrules to fit 1/4" fuel lines. Occasionally the seat of the sediment bowl or carburetor where the ferrule seats is worn or has been re-machined due to pitting. When these problems exist, the hex of the fuel line fitting bottoms out on the carburetor or sediment bowl before the ferrule tightens up on the fuel line when using conventional ferrules. These special ferrules will give you added length to compensate for that. Sold in pairs. U.S.A.