The 4 Ports C+L 1528~1610nm Polarization Maintaining Optical Circulator is a high-performance, non-reciprocal passive optical device that routes light sequentially from Port 1 → Port 2 → Port 3 → Port 4, while precisely maintaining the polarization state of the transmitted signal. Designed to operate across the C+L wavelength band (1528–1610 nm), it provides broadband performance, low insertion loss, high isolation, high return loss, and an excellent polarization extinction ratio (PER) — ensuring superior signal quality and system stability in advanced optical networks.