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 is 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. This kit contains a digital clock, and the instructions and everything you need (minus the spuds) to run it. Does not include potatoes. Turn the kids onto the notion of leaving a smaller carbon footprint. No batteries required.