This is an air experiment set where you can learn about the properties of air. You can immediately and easily start 6 different experiments and feel the properties of air, as well as the invisible workings and flow of air. In science for junior high school entrance exams, questions related to air are often asked. In particular, questions like "What happens when you compress trapped air or water?" and "How does the volume change when the temperature of air or water changes?" are frequently tested experimental themes. I bought two, and one has been stored at home unused. It is unopened. How about it if you don't mind? The outer box has some damage, but the inner box and contents are in good condition. This item can also be used for independent research projects.