EPIRB
EPIRB (Emergency Position-Indicating Radio Beacon) is a tracking transmitter which aids in the detection and location of crafts in distress. Strictly, it is radiobeacon that interfaces with Cospas-Sarsat, the international satellite system for search and rescue (SAR). When activated, such beacons send out a distress signal that, when detected, can be located and can be uniquely identified almost instantly.