Fiber optic adapter for connecting single-mode optical fibers with SC/UPC connectors. The high-quality ceramic ferrule, beveled at 8 degrees, reduces reflected signal attenuation. The locking mechanisms facilitate easy insertion and removal. The Duplex cable type is used in cable channels, distribution panels, and conduits with low mechanical loads. Single-mode optical fibers transmit only one light mode, with low reflection and reduced dispersion. SC connectors offer quick and easy connection, secure seating, and resistance to connection failures. They are used in telecommunications, video devices, media converters, LAN networks, WAN networks, CATV, sensor systems, measurement applications, and railway networks.