... RS485 Data 3 Levels Lightning Proof, Dual Powe 2CH Video Optical Transceiver Support Max. 20CH 232/485/CAN cable, 16CH Audio ... . Enhanced Functions.Remarks:1, Every unit includes a transmitter, a receiver and related accessories. Pls note following: 2, Power adaptors included ... fiber bi-directional transmission.6, RS232, RS485,RS422, etc Supportable Optical Transceiver