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! Caution: high voltage inspiration and fun! real science and real 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. Details: Multicolor 6.75" x 2.5" x 8.5" Does not include potatoes For ages 7 and up Contents: Digital clock with wires Pots Connecting wire Transparent tapes Copper and zinc strips Detailed instructions