This waggon is intended to be the driving force for my BR-E-75. 
Pictures of the model under construction will follow shortly.
It is modelled after the picture of the DRG luggage car No. 112 258 Dresden, type Pw4ü, in this folder.

Have a look at the various pictures in the picture gallery of the European Railway Server, 
with the keyword donnerbüchse (donnerbuechse, donnerbuchse)

http://www.railfaneurope.net/pix/pix.html

Enjoy!