4M Green Science Digital Potato Clock
Warning: Choking Hazard - Small Parts. Not for children under 3 years.7 years & up. Beep! Beep! It's not any ordinary alarm clock, it's a potato clock! The Potato Clock allows you to generate enough electricity to run a digital clock using two potatoes! Just push the zinc and copper electrodes into potatoes you provide causing an oxidation/reduction reaction that is converted to low voltage. Potatoes not included.