This versatile system will work on everything from .17 to .50 caliber and 12 to 20 gauge shotguns. Comes with an alignment target and durable storage pouch.Features : For use on .17 to .50 caliber and 12 to 20 gauge shotguns No metal on metal contact, will not scratch the finish of the barrel or damage your rifling Includes calibration target and storage pouch Unit includes (3) three lr44 alkaline button cell batteries