The Single Fiber 4 Channel Compact CWDM Mux Demux Module is a high-performance Coarse Wavelength Division Multiplexing (CWDM) device that utilizes single-fiber bidirectional transmission technology to multiplex and demultiplex four different wavelengths (typically in the 1270nm–1610nm range with 20nm spacing) over a single optical fiber, significantly improving fiber utilization. This compact module features low insertion loss, high channel isolation, and excellent stability, making it ideal for telecom networks, data center interconnects (DCI), 5G transport networks, and fiber access networks (FTTx). It supports ITU-T G.694.2 CWDM standard wavelengths and is compatible with LC/SC/FC connectors. Customization options are available for wavelength combinations, packaging formats, and fiber types to meet various network deployment needs.