Description: Teaching Aid: This lung breathing model is specially designed for classroom experiments and teaching, which can help students understanding the human respiratory systemEasy to Understand: Simply pull onto the bottom rubber section to view of how the lungs work, vividly showcasing diaphragm movements and lung expansion and contraction processesClassroom Teaching: The Lung demonstration model is rich details, clearly showing the structure and working principle of the human lungsEducational Toy: Easy to operate, students can do the experiment by themselves, improving their practical skills and scientific literacyNice Gift: The teaching toy can be used as nice gift for biology enthusiasts, or as part of a science education display Specification: Material: Glass Size Chart: 25cmx17cmx17cm/9.84inchx6.69inchx6.69inch Package Includes: 1 Lung Teaching Model Toy Note: Customer satisfaction is our primary concern. If the product is somehow cracked or broken during shipping, please feel free to contact us. We will try our best to give you a satisfactory solution.