Leitz CEYOO Synchronblitzer Flash Gun.  This was made between 1950-1959 and was for cameras with "F" synchronization. Accepts ES or SCC bulbs. It requires a 22.5V battery. The original Mallory M215 can be replaced by an 15F20 or 412A. Bulb adapter, sync cable original but dead battery and test bulb are all in the box. There is no reflector.