This round, water-powered clock requires no electricity or batteries, because it is powered by water alone. The clock runs off a simple galvanic cell battery that involves the emersion of a positive metal (such as copper) and a negative metal (such as zinc) in an electrolyte solution. That means this clock not only helps you save money, it is also eco-friendly. Your unique advertising message will be printed on the cap of the water tank and will thus, remind the recipient of your great service every time he or she refills the clock. In addition, the clock is equipped with a large LCD.