Like so many others, Heinrich Kleyer was a bicycle manufacturer in the late 1880s who switched to automobile production in the 1900s. During the First World War, Kleyer supported his country by producing airplane engines, trucks, transmissions for tanks, and other war-time materials. When war came to a close, automobile production resumed, and by 1928 the company had a workforce of 6,000 employees, and were making 60 cars a day. This was in addition to their bicycle and commercial vehicle construction.
The company had built a solid reputation and a business that was the third largest in German, behind BMW and Opel. In 1932, at the Geneva Motor Show, Adler introduced what would become their most successful and well-known vehicle, the Trumpf. Power was from a 1645cc engine and came in either saloon with two- or four-door configuration, a cabriolet, or open sports car. They had front-wheel drive, an all-steel body, and an complete independent suspension. It was sold under license in other countries; in France it was licensed by Rosengart and by Imperia in Belgium.
Adler produced a smaller version of the car, known as the Adler Trumpf Jr. Production of the Adler continued until the outbreak of WWII, while a few juniors were made until 1941.
The Adler Trumpf Jr. was produced from 1934 through 1941 with a total of 102,840 examples produced. Power was from a four-cylinder engine that displaced 995cc and produced 30 horsepower. Top speed was rather impressive, capable of achieving 60 miles per hour.