The eagle wings on the radiator tell us this is an Adler. Before the war this was the next step up from the smoky DKW
and this very special Kabriolet is definitely upmarket. Adler started car making in 1899 by using the De Dion design and soon earned a reputation for high quality. Most taxi cabs in Berlin before WW I carried the eagle badge. After the "Anschluss" the eminent designer Karl F. Jentschke from Steyr-Werke worked for Adler.