Tank manufacture (Chrysler). Traveling overhead hoists are used throughout the huge Chrysler tank arsenal in Detroit, for moving heavy castings from one production operation to another. These workers are removing the rotor casing for a 75 mm gun turret from a machine which grinds the outside rim. The twenty-eight ton "medium" tanks M-3s produced here carry 75 mm field guns and 37 mm anti-aircraft guns as well as several machine guns and other small arms