The BlackBox MED102A is their premium serial to single-mode fiber optic converter. It provides versatile connections between asychronous full- or half-duplex serial equipment using duplex single-mode fiber optic cable. The converter can also be set up in a multi-drop configuration to allow one serial device to communicate with multiple devices on a fiber ring. It supports mixed standards, which allows you to replace other converters and isolators and add the EMI/RFI protection inherent to fiber optic communications.