Profile: Hamilton Electronics designs and manufactures electronic products & presentation equipment for education and industry. We provide audio players/recorders, PA systems, digital cameras, listening centers, microphones, headphones, megaphones and video cameras. We also offer wired and wireless microphones. Our RH-3688 wireless mic system includes 2 two handheld UHF wireless transmitters with 9V batteries, wireless receiver-rackmountable and carrying case.