BSA help you get on paper without wasting shots. Comes with .177, .22, .66mm, .25, 6.5mm, .27, 7mm, .30, .32, .338, .35, .375, .44, .45, .50 Arbors. All packages in heavy duty hard case. Also, fits shotgun Gauges 10, 12, 16, 20, 28. Will not fit .410 Shotguns.