The TS-911 is a Chairman unit with voting function that can be connected to the conference system by a cable. It is equipped with a priority switch, allowing speech to take precedence over the Delegate unit. The TS-911 is directly connected to the TS-91981 or TS-919B4 Bridge unit, then to the TS-910 Central unit via the TS-918 Expansion unit. Either the standard type or long type can be selected for the microphone