Workers manufacturing 75 mm. cartridge cases at Buick plant
View of workers manufacturing 75 mm. cartridge cases at Buick plant. Label on back: "'Long past the experimental stage, the Buick process has been in successful operation for many months ...' Here steel cups for 75 mm cartridge cases are drawn while hot on crank presses, the first operation after the metal is extruded into the cup shape." Handwritten on back: "Conversion."