Reference:
EST-CU-8LCD
Control unit - 8 control slots and 4 function slots. Network-based system that allows configuration, diagnostics and management over Ethernet. Managing up to 254 devices on the network. 7 slots available for any speaker control board configuration, input and output control boards. 2 additional designated slots for audio input / output boards and input / output control boards. Up to 8 messages played simultaneously in different zones.