21 AMPLIFIERS, MICROPHONES AND INTERCOMMUNICATION EQUIPMENT; BURGLAR ALARMS AND PERSONAL SAFETY ALARMS; AUTOMATIC CLOSET LIGHTS; AUTOMATIC CIGARETTE LIGHTER PLUGS; AUTOMOBILE DEFROSTERS, VACUUM CLEANERS, IMMERSION HEATERS, IGNITION GUARDS, ANTENNA POWER BOOSTERS, AND TROUBLE LIGHTS; AND TELEPHONE EXTENSION JACKS, PLUGS, AND CORDS