The Tmh 985 is the most important vehicle for DFB's construction train operations. The typical use during the construction operations that take place in the summer season is mostly with the crane truck. This way, heavy machinery and equipment as well as construction materials can be brought to the construction sites, which are usually inaccessible from the road, without any effort. Since the line to Oberwald was put into operation, the vehicle is also used with the fire engine on operating days. The Tmh 985 cogwheel tractor was taken over from the former Brünig Railway on 18 September 2004. It was adapted to the needs of the DFB with a great deal of work.