This is an improved replacement for the original Nikon C-DSS Diascopic illuminator. This base is used with the Nikon SMZ series stereo microscopes to provide transmitted light illumination. These include the SMZ-800, SMZ 1000, SMZ-1500 and others. The high efficiency LED design gives a brighter, whiter light while using 1/10 the power of the original. Excessive heat from the light is eliminated and you will never have to change bulbs again. All of Nanodyne’s replacement microscope illuminators are designed and manufactured in Minneapolis, Minnesota USA.