The 12821 2.5V Pocket Scope Ophthalmoscope set includes a lightweight and compact ophthalmoscope with an AA-battery handle, two AA Alkaline batteries and a soft case. The ophthalmoscope uses halogen light for true tissue color and consistent, long-lasting illumination and has five aperture selections for general and specialist use. 48 lenses for better resolution. Its polarized filter reduces corneal reflection. Plus, 12 aperture/filter combinations for greater versatility: micro, small, and large spot sizes, cobalt blue filter for corneal exams, fixation target, and slit aperture, plus red-free filter and unfiltered halogen.