Great alternative to microscopes! This versatile, easy-to-use viewer allows young scientists to view our slide strips (which are actual images photographed through a microscope), 35 mm slides or conventional prepared slides-all with no additional light source needed! Made of sturdy plastic, the Investigator features a Snap-TightT tray to hold accessories. Includes two introductory slide strips and exciting Activity Guide. Classpack Set includes 10 slide viewers.