German-made professional key for business radios

This is a professional telegraph key that I received from a foreigner about 50 years ago. Professional telegraph keys are made with much greater precision and are superior to amateur radio keys.
The dimensions are approximately 19.5 cm in total length, 8 cm in width, and 6.6 cm in height.

This telegraph key appears to have been used in Europe. At the time, the previous owner had several and reportedly used this particular key very little.
The cable from the key output is considerably deteriorated due to age. Ultimately, I also never used the telegraph key after acquiring it.
As you can see from the photos, the main body inside the cover of this telegraph key is in its original condition and has not been modified. However, due to age, the cover and the base of the telegraph key have some blackening and scuff marks from friction. Therefore, I had the cover and base repainted to restore them.

Please note that the connecting plug at the end of the cable, which is normally required, is not included.

It is my belief that this telegraph key will be extremely difficult to obtain again in the future.

Please examine the photos and make your own judgment.