Extend Communications Up to 9 Miles!With a pair of these serial to fiber converters, any two pieces of asynchronous serial equipment can communicate at half or full duplex over two fibers at rates up to 460 kbps for RS-422/485 or 115.2 kbps for RS-232. Fiber lines are inherently resistant to EMI/RFI and transient surges, so they are ideal for data communications near heavy electrical equipment and other electrical or radio interference.