The one-off “Der Münchner” (“The one from Munich”) was the first locomotive to be built in Bavaria. It was ordered from Maffei for the initially privately operated route between Munich and Augsburg and later became the property of the state railway. A further 24 examples were also built by Kessler and Meyer under the designation A I.

Like the “Adler” they had the wheel arrangement 2-2-2 and a two-axle tender. Not only were parts from England used, the pear-shaped firebox is also a clear sign of the English influence. The power was provided by internal cylinders on the driving axle without wheel flanges, which, like all axles, was mounted inside the outer frame. Initially, wood was used as fuel, until later coal was used.

For the production of the 24 series locomotives, interchangeability of the parts was required, which was a novelty at the time. With the same external dimensions, the new locomotives had a 0.3 bar higher boiler pressure, larger cylinders and were slightly heavier. The unification brought with it a reduction in speed to 40 km/h, but greater traction was more important.

Although the first example was scrapped in 1871, some were sold and others rebuilt. During the conversion, the leading axle was exchanged for a second coupled axle. The last locomotive with the wheel arrangement 0-4-2 was retired in 1878, which was four years after the last locomotive in its original condition was scrapped.