Extralink multiplexer/demultiplexer is the basic element used to multiply the transmission capacity of a fiber optic track. It can be used both for newly built lines as well as for existing ones.
Extralink MUX/DEMUX CWDM is an 8-channel module operating in the 1470-1610nm wavelength range.
To use the waveform multiplier you have to use two d=modules at each end of the line.
Each output of the module is connected e.g. to a cwdm SFP insert operating at the appropriate wavelength.