The FPS-002 is an all fiber device that shifts or modulates phase shifts up to 75π at frequencies from DC to 20 kHz. It requires a lower half- wave voltage than the FPS-001: only 2V compared to up to 20V. Like the FPS-001, it is an all fiber design and offers the benefits of low loss and back reflection. Two different size packages are available to accommodate the bend diameter requirements of different fibers.