21 MICROPHONES, TELEPHONE PICKUP COIL, TRANSISTOR RADIO EARPHONES, WIRELESS MICROPHONES CONDENSERS, TRANSFORMERS, CAPACITORS, JACKS AND AND PLUGS, SPEAKERS, AND SPEAKER KITS, EARPHONES AND EARPHONE KITS, VOLUME CONTROLS AND VOLUME CONTROL KITS, RESISTORS AND RESISTOR KITS, TRANSISTOR INTERCOMS, FADER CONTROLS, TELEGRAPH KEYS, AND SWITCHES