This is a very rare camera, the famous 660 transparent autofocus.
It was a display model in a photo supplier's shop. Technically it is
functional, if a cartridge is in place, it ejects properly. Apparently,
not to harm the eyes of a spectator (it is indeed spectacular to see
everything operate), they disconnected the flash and changed the
circuit. Thus you can trigger without the flash being charged. If you
push the shutter button, everything starts on the inside, the shutter
opens and ejects a "photo". On the normal model the shutter must be held half way down while the flash is charging and the red light goes out; you can not trigger without the flash loaded.
is an object of decoration, the chamber itself is transparent. However,
the mirror is in place. For an experienced handyman it should be
possible just darken the chamber and plug the flash. This would be the
top of the top. But I'm not sure if this is really feasible.