The TCF-142 media converters are equipped with a multiple interface circuit that can handle RS-232 or RS-422/485 serial interfaces and multimode or single-mode fiber. TCF-142 converters are used to extend serial transmission up to 5km (TCF-142-M with multi-mode fiber) or up to 40km (TCF-142-S with single-mode fiber). The TCF-142 converters can be configured to convert either RS-232 signals, or RS-422/485 signals.