Optical Transceiver 20KM 64CH Video, 1CH Backward Data RS485 Data 3 Levels Lightning Proof, Dual Power Input, 64CH Video Digital Video Optical Transceiver 19" 4U Cabinet, Support Max. 160CH 232/485/CAN cable, 128CH Audio, 128CH Switching Values, 64CH Telephone, 392 Connectors, 8CH Independent Ethernet, Internet Management, 3 Levels Lightning Proof, Dual Power Input, Power Connection Protect. ...