I work at a technical school so have some people that know way more than I do about such things. I asked the question before making the purchase and was told that 50hz is the European standard, 60hz is the U.S. standard. I was told in no uncertain terms that putting a 50hz unit in the boat would be a bad thing, something about catching fire. As I was bothering the instructor at home on a weekend, I didn't ask for the details.

All that said, he could be wrong I suppose?