The Opel 4/12PS (also known as the Laubfrosch (treefrog))was the first german car that was assembled on a Ford inspired production line. It was a small two-seater that was introduced by Opel early 1924. The 4PS series continued with the 4/14, 4/16, 4/18 and ended with the 4/20 in 1931.
It was powered by an 1.0l one cylinder engine with 4hp. The top speed was 60km/h (37mph).