.22 Thompson breech
As can be seen in this view, the Thompson is not normally shot with open or 'iron' sights, it is intended to use telescopic sights (or other optical sights such as Red Dot) mounted on the receiver (the area above the breech). The gun is equipped with a 10 shot magazine as standard and is shown in the cocked, breech closed position with the safety catch off (ready to fire).
