A device to be used in a motor vehicle or motorboat for performing a wide variety of warning and monitoring functions. It includes apparatus to electrically connect to a positive battery cable (1,2), to a negative battery cable (3,4), and to the vehicle chassis (5,6); apparatus for warning sound and...http://www.google.de/patents/US4803459?utm_source=gb-gplus-sharePatent US4803459 - Electronic multi-purpose warning device for motor vehicles and motor boats
