Make magic with magnets with this incredible Electromagnet Science Kit! Build a doorbell, telegraph system and even a catapult all using the included magnets! Contents:Disc, latch and neodymium magnets, compass, straws, wires, sand paper, switch plates, wood screws, nails, light bulbs, battery holders iron filings, pre-drilled wood blocks, light emitting diode LEDAlso includes an experiment and project book