This CX-2x1-x (MUX/ DEMUX) and CX-1x2-x (DEMUX /MUX) module is Bi-directional Optical Multiplexer/De-multiplexer and will convert from two FP lasers or CWDM lasers wavelength to Multiplexed 1290nm-1350nm or 1510nm-1530nm range (MUX), or opposite direction (DEMUX) from Multiplexed 1290nm-1350nm or 1510nm-1530nm range signal to two FP lasers or CWDM lasers wavelength. This unit is compatible with all Meridian products as well as many other fiber transmission products in the market.