This category addresses communication devices used by people who are deaf, hard of hearing, visually impaired, or speech impaired to communicate over networks designed to carry voice. Whenever a device transmits and receives voice over a telecommunications network, it must then be able to support the hookup and successful interoperation of Teletypewriter-Assistive Technology (TTY-AT). This category includes telecommunications devices such as digital, analog, wire, wireless, and Internet-based products and devices such as PBX and telephone answering machines.
