This is an 8 channel CWDM mux cartridgethat operates over wavelengths 1291, 1331, 1371, 1411, 1471, 1511, 1551, 1591nm with pass ports using bidirectional transmission over single fiber. This unit can be used as either a multiplexer or de-multiplexer (mux/demux), and is a plug and play system. All of our mux/demux products are 100% compliant and provide a cost effective solution for your network upgrade needs. With our certification test program, we guarantee your product will work correctly the first time.