It is a small, battery powered emergency radio transmitting device carried on vessels for use in cases of distress at sea. It may be activated automatically or manually to transmit alerting and locating signals which assist search and rescue units in responding to and finding persons in distress. Recreational boaters who operate offshore or in remote areas are highly encouraged to have one.
Response time is the key to survival.
The sooner help arrives the better chance you have of surviving. Response times of less than an hour from time of alert to time of rescue have occurred. In the early 1970's emergency locator transmitting devices were developed for use in the aviation field. Frequently, however, no airplanes or satellites passed overhead and signals were not heard. The need for an ever present listening and positioning system became apparent.