4M Potato Clock 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. Challenge your child's imagination with 4M toys and kits. 4M educational toys cover a wide range of educational subjects and include science kits, arts and crafts kits, robotics kits, and more. 4M offers a wide range of toys and kits to let you build a clock, crochet a placemat, or turn your room into a planetarium--all in the name of making learning fun. This kit contains a digital clock, and the instructions and everything you need (minus the spuds) to run it Does not include potatoes Watch your child's delight and sense of accomplishment with the clock they create Turn the kids onto the notion of leaving a smaller carbon footprint No batteries required