The CDI-46 is an option module that provides Digital Paging Option, Ethernet Interface and RS-232 Interface for the 46/120 Mixer Amplifier Series. RJ-45 Digital Paging Interface RJ-45 Ethernet Interface (TCP/IP) RS-232 Interface The RJ-45 Digital Paging Interface allows connection of the Cloud PM-Series of paging microphones directly via Cat-5 to the CDI-46. The Ethernet and RS-232 Interfaces allow third party devices to control key functions including music source selection per zone, music level selection per zone and muting within the 46/120 Mixer Amplifier.