ELECTRICAL SOUND-AMPLIFYING DEVICES, LOUD-SPEAKING TELEPHONES, MARINE TELEPHONES, AIRCRAFT TELEPHONES, DESK TELEPHONES, AUDION FREQUENCY AMPLIFYING CABINETS, CONTROL BOXES FOR LOUD-SPEAKING TELEPHONES, LOUD-SPEAKING TRANSMITTERS, JUNCTION BOXES, ANTINOISE TELEPHONES, AND MASTER RINGERS FOR MARINE TELEPHONE EQUIPMENT