Dortmund was known for building plain family cars but they wanted to produce something to awe people and change that image. In 1938 they sent chief stylist Louis Gilmart to Czechoslovakia to check out Tatras, to France to see the Citroen Traction Avant and to USA to study the Chrysler Airflow and Lincoln-Zephyr models. Returning to Brunant he planned to make a car styled like (and to rival) the models he saw.
After much work the type 40 was unveiled in the fall of 1939. This car was very radical for several reasons. Firstly, it featured a streamlined body uncommon to Dortmunds (and most cars globally). It most striking feature was that it was a hardtop convertible; at the push of a button the rear trunklid opened and the metal roof would be stowed out of sight. In 1940 six models were put up for sale, at the hefty price of Th. 9,025 (about $3000). During the war, one of the cars was even partly disassembled and stowed in a cellar (in Donderstad) to prevent the Germans from "commandeering" it. One of the cars was scrapped in 1970 since it had rusted too much. Nowadays they are worth over 100,000 € each and many are in museums.]