Vintage "Hydrogen Air-Fuel Cell" demonstrator box made by Electro-Optical Systems of Pasadena, California, measuring 5.25″ x 7.75″ x 3.5″, featuring an air cathode (porous nickel with platinum black catalyst), electrolyte (potassium hydroxide impregnated in a matrix of sheet asbestos), and anode (Raney nickel), mounted together on a wooden base. Includes a typed sheet describing the hardware, potential performance, operating voltage, and other specifications. In fine condition.
