Nautilus LifeLine Marine GPS (nextGen) and Silicone Pouch w/ free DiveCatalog's Coil LanyardNautilus LifeLine Marine Rescue GPS The Nautilus Marine Rescue GPS is less than half the size of our original radio and is incredibly simple to use. Simply undo the latch and open, turn on, remove the antenna retainer, and press the red button. Thats it! Your GPS position accurate to 1. 5 metres and a man overboard distress message will be broadcast to all AIS equipped ships up to 34 miles away, as well as a special DSC message to the marine radio on