Abstract: There is disclosed an addressable device for receiving address coded signals from a central control unit. The device includes an electrical unit that is detachably connected to a base. The electrical unit has a switch for setting the address of the electrical unit. The base has an addressable key that is insertable into an opening in said switch when the addresses of the key and switch match and is not insertable when the addresses do not match. Alternatively, there is an addressable lock on one of the electrical unit and base and a separate addressable key on the other of the electrical unit and base.