Marcie - On our Voyager cruises, we've always used an extension cord to connect the waterpik in the bathroom (much less messy to use it in there than at the vanity table) to the 110 plug at the vanity table. I just measured the cord we use - it's a basic 15 ft. extension cord, quite compact and light. It doesn't have to be a 3-prong cord, since the waterpik is fairly low wattage. (If you plan to use a microwave in the bathroom to heat up pizzas or melt depilatory wax, you might need one of those heavy-duty 3-prong extension cords.) Cheers, Fred