Lens material: ABS. Preferred material, good quality, safe, durable 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: Will give your child a deeper 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: 2x 3 Times Bi-Convex Lens 2x Single Concave Lens 2x Acrylic Glass Brick 2x Single Convex Lens 2x Double Concave Lens 2x Triangular Prism 2x Three-Way Linear Light Source 2x 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.