Details: POOF-SLINKY: Crystal Radio Kit. Kids can build a working crystal radio that will pick up radio stations and allow them to experiment with radio waves while learning chemistry basics. No batteries or soldering are needed. This package contains: 1 diode, 1 base, four rubber bands, 1 tuning rod, 2 connecting wires, 1 coil wire, 1 sand paper, 1 earphone, three nuts, three bolts, four washers, 1 coil tube, 1 tuning ball and 1 instruction manual. Meets or exceeds ASTM F 963. Recommended for children ages 8 and up. WARNING: CHOKING HAZARD-Small parts. Not for children under 3 years.