Remember the golden age of radio? Crystal radio kit brings back the old memories and makes new ones! Build your own working radio! Pick up radio stations and experiment with radio waves. No batteries needed! Conduct experiments by trying different antennas and grounds. It"s a fun way to learn about radio waves! Instruction booklet included to help guide you through your experiments. Find a wide range of Poof-Slinky toys at Toys"R"Us.com! Poof-Slinky manufactures the POOF foam ball line and Slinky spring toys in the United States. Other products of POOF include the Classic Ideal construction toys and tabletop games, no-bake cooking kits, and science and activity kits. In the Spring of 2010 Poof-Slinky acquired Cadaco, a 75-year old manufacturer of a popular line of board games, including the famous Tripoley, the Ryan Oakes magic line, and the green activity/construction line EnviroBLOX; now called Stikits.