Regal 3300 Owner's Manual page 207

Shore Power
If equipped, your boat has a dual 30-amp shore power connection.
When connected to shore power, never swim anywhere near
the yacht. Stray voltage may leak from the shore power cord
and/or yacht shore power connector, which could result in
death or serious injury.
Never supply power to the water heater when it is empty. Fire
may result if the heating element is damaged, which could
result in death or serious injury.
Never alter shore power cable connectors. Use only compatible cable
connectors and shore power receptacles.
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WARNING
Features
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