the model shows in detail the cross-sectional structure of about the eighth thoracic vertebrae. According to the normal anatomical posture, the mediastinum is flattened to make a cross-sectional design, which reflects the cross-sectional relationship of the lung fissure, the arteries, veins, and bronchi, pleura, intercostal muscles and The front and left thoracic muscles can also show the structure and adjacent relationship of the spine and spinal cord through this plane, and the left and right atria and ventricles can be shown in the front.