Abstract: An electromagnetic lock comprised of an electromagnetic core fastened inside a casing to hold a coil unit in the grooves thereon, said casing being secured to a door frame or jamb, a armature plate connected to a door, and a control circuit to connect a power supply to said coil unit causing it to be energized for locking up with said armature plate, or to disconnect said power supply from said coil unit permitting said electromagnetic core to unlock from said armature plate.