Scientific apparatus and instruments, namely, electronic proximity sensors to detect objects; nautical apparatus and instruments, namely, electronic marine proximity sensors to detect objects for vessel protection; surveying instruments and apparatus; optical instruments and apparatus, namely, electronic optical receivers and transmitters for detecting objects and for measuring distance to objects; weighing apparatus and instruments; measuring apparatus and instruments, namely, electronic proximity sensors to measure the distance from the proximity sensor to objects; signaling apparatus and instruments, namely, apparatus in the nature of a warning horn, warning light or electronic warning message for emitting a warning output when a potential hazard is detected; checking apparatus and instruments, namely, electronic apparatus in the nature of a sensor or sensors for verifying the proximity to nearby objects such as vessels, oil rigs, docks, quaysides and other marine structures; life-saving apparatus and instruments, namely, electronic proximity sensors to measure the range to nearby objects and emit a warning output when a potential hazard is detected; data processing equipment, namely, couplers; computers; computer software in the field of marine vessel protection for use in measuring the range to nearby objects and emitting a warning when a potential hazard is detected