The project was eventually abandoned after Salomon Kahn was arrested and nobody else showed any interest in the studio camera. Of the 14 prototypes that were built, one still exists: it currently belongs to the Municipal Museum of Braunschweig. Rolleicord In 1933, the Rolleicord, a cheaper version of the Rolleiflex, came onto the market. It had simpler Zeiss Triotar Lens, a steel back-plate, and a knob instead of a handle for winding on the film. The Rolleicord 1 cost ; altogether 2,699,505 Rolleicords were manufactured until production ceased in 1976. The later models (III - VB) uses Schneider Xenar lenses that have better optics. Rolleiflex Automat The release of the Rolleiflex Automat in the middle of June 1937 marked another significant milestone for Franke & Heidecke. Prior to this, after taking a picture, two separate steps were required to advance the film and cock the shutter. The Rolleiflex Automat combined the two, whereby advancing the film automatically cocked the shutter. Not only did this innovation speed up the whole process, it also eliminated accidental double exposures resulting from inadvertently forgetting to wind on the film. It also had a film-feeler mechanism that automatically started the counter, so no red window was needed. The Rolleiflex Automat won the Grand Prix award at the Paris World's Fair in 1937, which generated a lot of interest. The company founders we so taken with their new creation that they immediately commissioned the construction of a second factory. The new factory, comprising three floors with a combined production area of , provided sufficient space to house a further 700 workers. It was completed in 1938, and by the end of that year the 300,000th camera had come off the production line. In retrospect, Reinhold Heidecke regarded the Rolleiflex Automat as his favourite camera. World War II During World War II, the company was required by the Nazis to support the war economy. As a result, Rollei was unable to develop any new models from 1940, and production of its stereo camera finally came to an end. Rollei also suffered massive losses resulting from its inability to collect monies owed by debtors from "enemy states". Furthermore, bureaucratic formalities and controls hindered exports to neutral countries. This situation, combined with the collapse in overseas trade, forced Paul Franke to reduce the workforce to 600 people. Armaments production Alongside its renowned cameras, Rollei – like its neighbour Voigtländer