Environmentally Friendly Water Energy Clock Size: 88 x 82 x 77 mm Weight: 80g (excluding packaging) Power Supply Mode: Water-powered Working Principle: This clock operates without batteries. Simply fill the reservoir on the back with water to activate the time and date display. It can function for several weeks without refilling. Electricity is generated through a chemical reaction triggered by water. The reaction involves metal elements from the top 20 of the periodic table, contains no heavy metals, and is environmentally safe. Instructions: The device works with tap water. If the display becomes dim or disappears, add water or another non-corrosive liquid until the positive and negative electrodes in the container are fully submerged. This will restore normal operation.