Fiber Optic Cleaner Pen is designed to specially work well with the female connectors, this instrument cleans the ferrule end faces removing dust, oil, and other debris without nicking or scratching the end face. One Click 2.5mm SC ST FC Connector Fiber Optic Cleaner and SC/ST/FC Optical Fiber Cleaning Pen,Super high quality. Work well with the SC FC and ST connectors, this instrument cleans the ferrule end faces, removing dust, oil, and other debris without nicking or scratching the end face.