Wagener built a number of light sportsplanes between the wars. The model depicted is in fact the HW 4a which was powered by a 20hp Festenberg-Pakisch engine which differed from the original HW.4 which was powered a Ursinus U2. The aircraft weighed approximately 400kg and had a maximum speed of 110 km/h. The span was 9.00m and the length 5.70m