Lens material: ABS. Preferred material, good quality, safe, durable and functional. Batteries required: 2 AAA batteries (not included)Three-way linear : The direction of the light can be adjusted with a screwdriver.Optical experiments: refraction of light, convex lens refraction, lens refraction, prism refraction, plane mirror reflection, diffuse reflection, convex mirror reflection, concave mirror reflection, etc.Physical Optics Experiment Set: Will give your child a understanding of physical optics, making learning easier and more enjoyable!Name: Optical Experiment KitColour:WhiteMaterial:ABSSize: 24 x 14 x 3cmPackage Contents:1x 3 Bi-Convex Lens1x Single Concave Lens1x Acrylic Glass Brick1x Single Convex Lens1x Double Concave Lens1x Triangular Prism1x Three-Way Linear 1x Multifunctional ReflectorOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.", Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.