1m -0/+0.1m long, Master reference patchcord, 3 mm OD jacketed (blue color), 3.5/125µ 532nm PM fiber patchcord, terminated with super FC/PC connectors on both ends, which are pre-aligned and locked on the slow axis. ER=25dB minimum with +/-1.5degree polarization angle tolerance (Optically) and while there is no external stress is applied onto fiber.