Precision Pours offers Rack & Pour measuring heads as a separate purchase for users who wish to stock varied shot sizes, upgrade from non-metered heads to metered heads, or simply replace old heads with new heads after heavy usage. Each measuring head includes a rubber cork with fins installed on the stem (the portion inserted into the bottles). An additional natural cork is included which can replace the rubber cork and allow the user to fit the measuring head into bottles with larger diameter openings.