Blue Personal Locator Beacons

PLBs send a one-way 406 MHz SOS with GPS location to rescue agencies and require no subscription, making them ideal for pure emergency signaling. Satellite messengers like the Garmin inReach Mini add two-way messaging, tracking, and navigation on a subscription plan when you need regular check-ins or weather info.

Yes—many PLBs are designed for marine use with buoyant bodies and waterproof housings rated to 15 meters (50 feet), and models like the ACR ResQLink+ are explicitly buoyant for water recovery. They also include high-visibility strobes and 121.5 MHz homing to help rescuers locate you in rough conditions.

Check the manufacturer battery expiration and perform periodic function tests as recommended, since PLBs typically have a 7-year shelf life battery and require replacement after that interval. Also register the device with NOAA for U.S. PLBs and confirm satellite compatibility (COSPAS‑SARSAT) so your distress signal routes correctly.

Choose a compact, pocketable geometry and secure mounting—many units are under 5.5 oz and models like the Ocean Signal rescueME PLB1 measure about 3 x 2.1 x 1.3 inches for easy pocket or strap mounting. Retractable antennas and multifunction clips reduce snag risk, and buoyant models are better if you expect water exposure.

PLBs use GPS/Galileo positioning with typical accuracy within about 100 meters, and they transmit a 406 MHz distress signal plus 121.5 MHz homing to aid rescuers. Expect a minimum transmit time designed to last at least 24 hours after activation so teams can find your location.