ABIS Inc | VoIP Provider, Services and Repairs United States
Business telephone & telecommunication installation and services for Nortel phone systems, Avaya phone systems. Dallas VoIP products, services & installation
This is a way of communicating on the half-duplex communication line, includes receiving and transmitting devices (walkie-talkie) by the way of pressing the button for switching to the voice mode or transition to the listening mode. It works as a radio speaker; one can talk by pressing the button and can listen to a voice message by releasing the button.