This traditional 4 Class (measured diagonally) slide and filmstrip viewer has been upgraded to feature 4 tru-color LEDs for bright, even illumination of slides or filmstrips. The four LEDs provide superior color rendition to the old incandescent bulb. Still has a glass lens providing a 3X magnification of the image and the quick eject button that allows the slides to stack in the collection tray. Uses 4 AA batteries (not included) or can be plugged into a standard USB power outlet.