The T020-001-ST9 FC to ST 9/125 Adapter converts a native FC fiber female port on the T020-001-PSF Multi-Function Optical Fiber Cable Tester to an ST female port for 9/125 singlemode cable testing. “9/125” is clearly labeled on the unit to differentiate the T020-001-ST9 from other adapters. Included dust caps keep the connectors clean when not in use.