This Lee Inline Bullet Feeder Magazine is an extra gatling style magazine for the Lee Inline Bullet Feeder Kit. These spare magazines work great to have another magazine ready to load to keep your reloading process moving swiftly and efficiently. Sizing Information:Large: works with bullet diameters .390 to .463. 40 CAL 45 CALMedium: works with bullet diameters .300 to .372. 30 CAL 35 CALSmall: works with bullet diameters .220 to .273. 22 CAL 24 CAL 26 CAL