This 2-wire Clear-Com/RTS party line interface (dual) connects two 2-wire full duplex partyline circuits with matrix. The interface supports Clear-Com signaling to and from the matrix system, deriving its power from the external partyline circuit. Levels and cable nulling are completely adjustable. The CCI-22 functions with Clear-Com and other two-wire intercom systems. Does not power the partylines attached to CCI-22 modules. These require Encore Master Station PSUs such as the PK-7, PS-702 or MS-702.