The five tower railcars of the series 704, delivered between 1977 and 1978, were developed as successors to the series 701/702 based on the railcar series 627.0/628.0. The two-engine vehicles were capable of speeds up to 140 km/h and could still reach 100 km/h with a trailing load on a 5 ‰ gradient. This allowed them to quickly arrive at the job site, and their excellent technical equipment made them versatile for use everywhere. They often operated alongside overhead line construction vehicles or additional equipment cars. Throughout their over 30 years of service, they frequently changed the depots where they were stationed, depending on the work situation and the duration of major construction projects in the rail network, enabling rapid deployment from various locations across Germany. Initially, the operators were often affected by engine exhaust fumes, so in 1986, the 704 series received new, less polluting engines. Additionally, exhaust pipes were routed along the left and right sides of the roof, allowing for remote-controlled diversion of exhaust gases in the desired direction depending on wind and air conditions. Due to the lack of spare parts after the retirement of the series 627.0 and 628.0, the tower railcars were decommissioned and collected in Cottbus by 2012. They remained there for several years for sale but found no buyers. The last operational vehicle was the 704 002-5, which was transferred in January 2012 from its last operating depot in Ludwigshafen to Karlsruhe and then to Cottbus. Unfortunately, all five tower railcars were dismantled, and none have been preserved for museum purposes. Our model was delivered on April 11, 1978, as the fourth vehicle of the series 704 to the depot in Osnabrück, where it remained until November 1986. It was then relocated to the depot in Würzburg, where it stayed until its retirement, after a brief detour to the depot in Nürnberg 2 from February 2004 to August 2006.