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Small and light, the McMurdo Fast Find 220 personal locator beacon (PLB) with GPS provides virtually global coverage to find you quickly in an emergency, whether you're at sea or on a remote mountain. Powerful 5-watt transmitter sends a 406MHz signal to COSPAS-SARSAT satellites to pinpoint your location anywhere on the Earth's surface-no subscription required. Built-in 50-channel GPS with ceramic patch antenna includes your coordinates in the emergency satellite transmission to identify your exact position. Signal identifies your unique PLB and gives Search and Rescue the PLB owner's data and family contacts (requires free registration with NOAA or other national authorities). Simultaneously transmits a local, 121.5MHz homing signal to help rescuers speed up the response time once they approach your location. Once activated, the Fast Find 220 signals will continue to transmit for at least 24 hrs. Simple 3-stage activation: pull antenna cover off, unwrap antenna until it stands vertical and press the "ON" button (antenna cover must be replaced by manufacturer after use). Indicator light flashes twice per second when the PLB is searching for a GPS position fix and once per 3 seconds when a GPS fix has been acquired. A long flash followed by 3 rapid flashes every 50 seconds indicates that the PLB has transmitted a distress signal along with your current GPS coordinates. FastFind 220 does not have an exposed "ON" button; along with a breakaway panel over the antenna, this helps prevent the unit from accidentally activating. First emergency alert transmission occurs 50 seconds after activation, allowing time for the unit to be switched off before the alert is sent. LED signal light can be manually activated and blinks an SOS pattern to help searchers locate you visually during a nighttime rescue. Sealed construction allows FastFind 220 to be immersed to 10m (33 ft.