Be a scientist as you discover how to power this digital clock using potatoes. Experiment to find out what other substances will power the clock - you'll be amazed! 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 the potatoes causing an oxidation/reduction reaction that is converted to low voltage. Kit contains digital clock with wires, pots, connecting wire, transparent tapes, copper and zinc strips, and detailed instructions. Does not include potatoes.