803-39 - Microphones and Related Equipment (Not Wireless Systems): Chestsets, Earphones, Handsets, Headphones, etc.
803-10 - Cartridges (Microphone, Phonograph, etc.), Needles, Pickup Arms, Styli, etc.
803-40 - Microphones and Related Equipment (Wireless Systems): Chestsets, Earphones, Handsets, Headphones, etc.
840-14 - Audio Equipment and Accessories, Television (Microphones, Mixers, and Amplifiers)
655-15 - Camera Accessories: Batteries, Exposure Meters (Light Meters), Flash Equipment and Bar Lights (See Class 285 for Lamps), Power Packs and Chargers, Tripods, etc.
939-77 - Sound Equipment (Including Microphones, Speakers, Recording Equipment, etc.) Maintenance and Repair