Lens material: ABS. Preferred material, , safe, and functional. Batteries required: 2 AAA batteries (not included) Three-way linear light source: 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: give your child a understanding of physical optics, making learning easier and more enjoyable! Name: Optical Experiment Kit Colour:White Material:ABS Size: 24 x 14 x 3cm Package Contents: 5x 3 Times Bi-Convex Lens 5x Single Concave Lens 5x Acrylic Glass Brick 5x Single Convex Lens 5x Double Concave Lens 5x Triangular Prism 5x Three-Way Linear Light Source 5x Multifunctional Reflector Only 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.