It's mainly used for some practical parts of the initial AMT apprenticeship in Germany, which is not type specific at all. It serves to teach the apprentices the basics of handling aircraft and performing maintenance tasks, be it the simplest things like opening doors, applying electrical power, removing access panels etc. It's also the subject of the apprentices' practical final exams, which are often in the form of performing shock strut nitrogen service, minor part replacements on the a/c packs or comparable tasks.