Marketed with an eye towards riot control and prison population management, the Peters-Thompson 45 Auto Shot Cartridge loads a cardboard "pill" of 120 pellets of #8 birdshot into a double crimped 45 ACP casing. Though slightly larger than a standard 45 round, the only modification needed to run the Peters-Thompson through Thompson's SMGs and Carbines was a special elongated magazine. The combination would allow a Thompson gunner to switch their weapon from a pistol caliber machine gun to a straight pull small bore shotgun by swapping the magazine, giving a less-lethal option while still having deadly force on hand and ready. Very similar in appearance to the standard magazine, the shot magazine is blued steel with the legend "PATENTED-AUG.-24-1920/FOR 18 SHOT CARTRIDGES/AUG.-24-1920-JAN.-11-1921" stamped on the front. The box is brown paper construction, with "PETERS/RUSTLESS-RIOT CARTRIDGES" above an illustration of the Auto Shot round.