... ThyssenKrupp Elevator Interphone,Five Party Talkback TK-T12(1-1)A Details Products Description:Technical parameters: 1.Various Type: ... communication:Duplex and group control.3.The composing form is twowire system,three types voltage,24V,12V,6V;Be ... free combination,reliable performance and clear communication. About USSUNNY is a 20-year professional manufacturer specialized in designing and producing ...