What! No Batteries? Be a scientist as you discover how to power this digital clock using potatoes. You may know potatoes as a good source of potassium, but did you know they can be used to power an alarm clock? Experiment to find out what other substances will power the clock ? you?ll be amazed! Caution: High Voltage Inspiration and Fun! The two Potato Clock allows you to generate enough electricity to run a digital clock using potatoes! Just push the zinc and copper electrodes into the potatoes causing an oxidation/reduction reaction that is converted to low voltage. Watch your child”s delight and sense of accomplishment with the clock they create. The 4M Potato Clock teaches young minds the value of green energy in an illuminating way. The Potato Clock uses a pair of ordinary spuds to power a digital clock. This kit includes a digital clock, wires and prongs; two potatoes are all that’s needed to create a working clock. This kit is ideal for young science enthusiasts, and offers a valuable lesson on the transformative power of green science. Detailed assembly instructions included. No batteries required.