Upgraded Model: The junior high school physics optics experiment kit is a new upgraded model, suitable for students who are interested in exploring optical principlesComprehensive Content: The physics optics experiment kits covers a wide range of topics such as imaging, light reflection and refraction, lens imaging rules, direct light projection, the three primary colors of light, and convex and concave lens imaging rules Teaching Aids: This physical light reflection demonstration model is an teaching aid in the classroom. It helps students effectively understand the principle of light refractionQuality Materials: Optical experiment tool made of quality materials, it is smooth and burr freely and sturdy. The kit is easy to assemble and does not require any additional accessoriesPractical Science Kit: This physical optics experiment science kits is simple and practical, suitable for classroom assignments Size Chart: 53cmx12cmx14cm/20.87inchx4.72inchx5.51inch Package Includes: 1Physics Optics Experiment Kits Note: 1.This is not infant toy , please take away from children to avoid eating.2.Please allow slightly errors 1-2cm differences due to manual measurement.