In type I, the Grand Duchy of Mecklenburg Friedrich-Franz-Eisenbahn combined a total of six locomotives with a 2-2-2 wheel arrangement, which were primarily used to pull passenger trains. Among them was the “Marschall Vorwärts”, which had been named after Field Marshal Blücher. It was the first machine to be used on the Hagenow - Schwerin - Wismar line by what was then still known as the Mecklenburg Railway Company. It connected to the Berlin-Hamburg line that had just been opened by Prussia.
Although the first example was built as early as 1848, the design of the locomotives was already based on aspects that were more frequently encountered in later locomotives. These included, above all, an inside forked frame and cylinders mounted horizontally on the outside. The valve gear was arranged inside and designed according to the Stephenson design.
Since the procurement period stretched over 15 years, some machines differed from the others. Thus, the cylinders of the fourth and fifth machines were attached inclined to the smoke box. The sixth and last saw the boiler expanded from two to three shots and the firebox extended backwards over the trailing axle to provide a larger grate area.
Although they only had a single driven axle, the locomotives were able to last a long time. This is mainly due to the fact that the Mecklenburg network was in flat country and the train weights remained relatively low due to the low population density. The first two machines were retired in 1890 and 1894, the rest followed in the years 1898 to 1901.