The Fiber Master Unit (FMU) is used to convert signals from to light when fibers fed repeaters are used. The FMU is most often connected to base station. Optical fiber delivers radio signals to a distance of up to 20Km. Built-in NMS for remote control and monitoring of the paired units and optic fiber link continuity. Full Aluminum rack structure with front slot in design for each laser module, easy field maintenance and network upgrade.