[Educational Tool]: Physics Optical Experiment Set is designed to clearly demonstrate the phenomenon that light changes its propagation direction when it moves from 1 medium to another, causes refraction at the of different media, and the phenomenon that light returns to its original direction in the material when it propagates to different materials [Material]: Refraction and Reflection of Light is made of plastic, ensuring long term use and wear resistance [Compact Size]: Convex Lens and Small Hole Imaging Experiment's which is compact and easy to store or carry, suitable for classroom demonstrations or learning courses [Versatile Use]: Teaching Aid is an teaching aid for secondary school physics education, making complex optical principles easy to understand through hands on experiments Note:This is not infant toy , please take away from children to avoid eating. Please note: the physical slightly color difference or difference, does not affect the use, please do not mind, thank you! Colour: As Shown Material: plastic Package Contents: 1 x Physics Optical Experiment Set 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.