Fiberers DWDM filter dense wavelength division multiplexer (DWDM) utilizes thin film coating technology and proprietary design of non-flux metal bonding micro optics packaging to achieve optical add and drop at the ITU wavelengths. It provides ITU channel center wavelength, low insertion loss, high channel isolation, wide pass band, low temperature sensitivity and epoxy free optical path. It can be used for wavelength add/drop in telecommunication network system. All Fiberer DWDM filter are Telcordia qualification tested.