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I have had Garmin GPS III for 2+ years and it is without question a valuable piece of equipment. When you turn this unit on as you launch your boat, it will acquire satelites and show you an overhead view(map) of where you are. If you do nothing else, as you leave the port it will follow you and create a "bread crumb" trail showing where you've been. If the fog rolls in or you get lost, just follow the bread crumb trail back to the harbor. No numbers to read or track, though it has all those features, too. It sits on the dash or can be hand held. Operates on battery's or 12volt plug-in. Would also be great for hiking and hunting.
Good Luck.


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