LOK-A-BIN

INTERLOCKING SYSTEMS FOR INTERLOCKING THE WHITH LIGHTS, ENTRANCE DOORS AND FILM STORAGE BINS OF DARK-ROOMS, AND COMPONENTS OF SUCH SYSTEMS-NAMELY, LOCKING HARDWARE AND MECHANISMS AND ELECTRIC CIRCUITRY AND COMPONENTS FOR LOCKING AND UNLOCKING FILM BINS AND ENTRANCE DOORS AND FOR TURNING ON AND OFF LIGHTS IN RESPONSE TO PREDETERMINED CONDITIONS