This listing is for a Vintage Japanese Microscope Illuminator Unit Light Lamp Japan Battery Operated in good, tested as working, vintage used condition. Some plastic wear and tear (see photos). The connection at the switch is weak and needs to be restored/improved as the lamp is dim otherwise. Battery box had some light corrosion inside and has been cleaned/neutralized with baking soda and a brush. Measures roughly 2.5" across the front, just over 2.25" front to back, 1.25" high at rail where it slides below the microscope plate, the tracks it slides into are approx 1.85" apart at outside and they're triangled on the inner side just over 1.5" apart. Not sure what microscope it fits.