PMJ-A3A Fibre optic patch cable with FC/PC connectors. • The cable jacket is marked PMJ-A3A, 3A-633-4/125-3A-3-1, which suggests this is a polarization-maintaining (PM) fiber optic cable. The “633” likely indicates it’s optimized for use at 633 nm wavelength (common for HeNe lasers or similar sources).
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