From 1957 onwards, motorized railway service units from the OeBB's Woerth plant in St. Poelten/Lower Austria were built in large numbers of the X 625 and X 626 series. These "motor radars" or "motor railway vehicles" have been and are still mainly used in road service today. They were or are found in different designs with different side cars or railway service flat cars on almost all railway stations of Austria - both on normal gauge and on narrow gauge tracks. They are also used in many private and museum railways.The difference between the X 625 and X 626 series is the installation of a stronger motor on the X 626. Since the vehicles in normal track design are also capable, if required, of transporting up to two goods wagons, these are not only a center buffer couplingAlso fitted with a normal traction and shock system. The vehicles for the narrow gauge have only the center buffer coupling. Exceptions are made in the case of former normal-gauge draisins, which were later relayed to