CWDM Optical Add/Drop multiplexer (OADM) is a passive optical device used in WDM networks for adding and dropping one/multiple CWDM channels into one or two fibers, while allowing the rest of the wavelengths bypass to the desired destination. WDM OADM modules are available in single-sided (east or west) and dual-sided (east and west) configurations supporting up to four wavelengths. AscentOptics provide high-performance CWDM OADM, including dual fiber 2 channels and 4 channels, single fiber 1 channel, using LGX packaging.