TALKBACK MIC对讲麦克风
sound talkback演播室对讲
Talkback Systems对讲系统
Talkback linkage对讲联动型电梯控制系统
elevator talkback电梯对讲
wireless talkback无线对讲
Talkback Functions对讲功能
TB talkback对讲回送;对于讲回送
talkback speaker联络电话扩音器