Abstract: A key composed of a body with recesses which can be filled with magnetized disks, arranged in a combination of norths and/or souths and/or lack thereof, and with a sliding lid holding the magnetic disks in the recesses. The lock has one or two sets of magnetic sensors geometrically ordered according to the refillable recesses. When the key is placed adjacent to the series of magnetic lock sensors, the sensors detect the magnetized disks, pass the detected signal to a conventional converter-codifier circuit that generates a code that is sent, by cable or radio, to a station which interprets the code and, if correct, allows access.