Note the rather unusual wide F-Holes.
Hofner's active electronics Treble Boost/Fuzz circuit has been built into this guitar. Note the lack of binding around the back of the 2" deep body.
A bolt-on neck is used on this prototype.
The clue to this being a Hofner prototype. Ernst Brem's music shop was located at Lichtenfels, which is very close to the old Hofner factory at Bubenreuth. Following enquiries made by Sascha and his friend Stefan, Herr Brem has confirmed that he did indeed have excellent contacts with Hofner and also remembers that they did supply him from time to time with prototype and special order guitars.