Rescue Radios
The Garmin inReach Mini 2 uses the Iridium satellite network to provide two way SMS text messaging and interactive SOS alerts with GPS position from any location on the globe and requires a paid subscription. The Nautilus Marine Rescue GPS sends a digital distress message with your GPS position to any vessel that has a modern marine VHF radio within line of sight and does not require any subscription. Although they transmit and receive at the surface only, both devices are capable of being carried by divers to extreme depths.