This demonstration video will show youthe features of the Nautilus Lifeline GPS Radio. Easy to use - with a push of a button you can talk to every boat around you with an VHF radio within an 8 mile range On the surface talk diver to diver when both are carrying Nautilus Lifeline´s. The latest in marine radio technology. Features DSC (Digital Selective Calling) - part of a global upgrade in maritime distress communications. Full featured marine VHF radio and GPS USB cable plugs into your computer and charges the internal battery. Easily attaches to your D-ring. 24 hour battery life in emergency mode Position indicator light. Depth rated to 425 feet.