Each set includes 1 LED Viewer (100 x 95mm), 5 Life Cycle Slides (73 x 73 x 9mm) containing Dragonfly Life Cycle, Spotted Lanternfly Life Cycle, Grasshopper Life Cycle, Honey Bee Life Cycle and Cabbage White Butterfly Life Cycle. Also, includes a teacher's guide. The LED Slide Viewer adds another dimension to the Mini Beast Specimens. Lights on the sides and bottom of the viewer illuminate the specimen slides in a way children will find amazing. Powered by an alkaline button battery secured by a screw, the Slide Viewer offers over 800 hours of viewing time.