Bsa bs30 boresighter kit w/standard & 12ga.Studs FEATURES-Will help you get on paper without wasting shots-All packaged in heavy duty hard caseComes with the following Arbors:-.177, .22, 6mm, .25, 6.5mm, .27, 7mm, .30, .32, .338, .35, .375, .44, .45, .50Also fits shotgun guages:-12, 12, 16, 20, 28Will NOT fit .410 shotguns Other Features: Heavy hard case incl'd adj bore stud from 20ga - 12ga 30mm collimator 16 arbors