21 AMPLIFIERS, RADIO RECEIVERS, RADIO TRANSCEIVERS, WALKIE-TALKIES, HEADPHONES, INTERCOMS, TUNERS, MICROPHONES, SPEAKERS, OUTLETS, CABLES, EARPHONES, CAPACITORS, ANTENNAS, INTERFERENCE FILTERS, SWITCHES, PLUGS, JACKS, PLUG-JACK ADAPTERS, TELEPHONE PICK-UPS, AND TAPE DEMAGNETIZERS