The IR-801AF US is an Audio Interface Unit designed for use in a school classroom with the legacyIR-310M Ypush button Infrared Wireless Microphone. It connects between the IR-802T Infrared Wireless Tuner and IR-820SP Infrared Speaker by a single CAT-5 UTP cable. It has an analogue audio output and a contact output. Permits connecting with external equipment, like a paging system, strobe light or message repeater and can allow the function push button to act as a panic callback button to the office. Not for use with IR-310M Y PQD00.