Vivitar Refractor Telescope/Microscope Combo 20x/30x/40x with Tripod: * For ages 6 years and older * Objective diameter: 50mm * Focus length: 170mm * Magnification: 20x, 30x, 40x * Built-in compass * Set includes specimen slide, blank slides, slide covers, specimen collection vials and tweezers * 1-year limited warranty * Model# VIV-TELMIC-20