Polarization controllers are used to manually align the polarization axes in optical fibers.
The PolaRITE series from General Photonics changes the alignment of the polarization axes by placing mechanical pressure and torsion on the fiber.
There are versions available for the insertion of fibers with a diameter of 250 µm and tight buffer fibers with a diameter of 900 µm, as well as versions with a firmly installed fiber that has a pigtail or direct fiber connection. These products are designated PLC (polarization controller).