Prussia, Alsace-Lorraine, Baden, Württemberg G 12 Saxon XIII H (1919 version) DRG Class 58.2–5/10–21 ÖBB Class 658 PKP Class Ty1 SNCF 150 C JŽ class 36 État-Belge Type 92
It had been shown during the First World War that, from a servicing and maintenance point of view, it was a great disadvantage for each state railway to have its own locomotive classes with no standardization. Even spare parts for locos of the same class often did not fit their sister locos. In addition, the military railways needed a fast, powerful, goods locomotive that did not have a high axle load.