78584677
Mar 10, 2005
Jun 5, 2007
Wireless group amplification systems comprised primarily of wireless amplifiers, transmitters and speakers to improve acoustics and hearing and to amplify and clarify voices in the classroom
Electrical and Scientific ApparatusWireless group auditory trainers, namely, auditory headset devices used to improve instruction for students with normal hearing, hearing impairment, and other disabilities
Medical Apparatus