The American Fibertek 05B Series transmits single direction audio on one multimode optical fiber at 850 nm. This product line has the option for 1300 nm multimode or singlemode optics. This system requires no field adjustments at installation or additional maintenance thereafter. Diagnostic indicators provide a quick visual indication of system status. Equipment may be ordered as stand alone modules or rack cards that are mounted in the American Fibertek Card Cages: SR-20/2 or SR-20R/1.