The BFG Caliber 866 is simple pin lever movement, which at least uses a yoke winding system. It has got only a single-sided shock protection.
The gear construction is pretty unusual, since one reduction step is missing, and the third(!) wheel is directly driven by the mainspring barrel, which is unusually large and has got a diameter of more than half of the main plate. This can only be acieved beause the minute hand is indirectly driven on the dial side.
Another odd construction is that one of the indirectly driven center second: The outer ring of the fourth wheel directly drives the outer ring of the center second wheel.
This movement is also available with a smaller main plate, using the same caliber number.
This movement was kindly donated by Klaus Brunnemer. Thank you very much!