The AT3 is a telephone amplifier for phone systems requiring a PJ 327 plug prong interface. It is a unique product that offers a field replaceable headset cord and a 90° bend to minimize space and position the controls for easy access. Additional product features include full range volume control, voice switching to further reduce background noise when the agent is not speaking, GN Netcom's FailSafe Compression to ensure constant speaker output, as well as the patent pending circuit that precisely intercepts acoustic spikes.The AT3 telephone is a mute version.