suitable for Water Powered Electronic Table Clock Digital Children Alarm Clock With Calendar Christmas Gift For Kids H-CHENG DU SI XI Product DescriptionProduct name: Environmentally friendly water energy clockSize: 88*82*77MMWeight: 80g (excluding outsourcing)Power supply mode: water power supplyworking principle:The water energy clock does not need batteries at all, as long as the bottle on the back of the clock is filled with water, the time and date can be clearly displayed, and it does not need to be refilled for several weeks. The source of electricity, water, triggers internal chemical reactions. The chemical reaction is mainly the metal elements in the top 20 of the periodic table, does not contain heavy metals, and is harmless to the environment.Instructions:This product can work normally by adding tap water. If the display of the product is dim or disappears, you need to add water or other liquids (except corrosive liquids) until the liquid fills the positive and negative electrodes in the container to work normally.Note: (different types of perfume can be added according to personal preference) Please pay attention to the title and description when buying, and pay attention to the title and description when buying.