This simple model demonstrates the functioning of lungs for students. It depicts how the lungs are emptied and filled with air by the relaxation and contraction of the diaphragm muscle.Consists of: Two balloons attached to a Y-tube simulate the lungsThe chest cavity is a bell jar with open top and stout latex rubber sheet that acts as the diaphragm. As the diaphragm is pulled downward the atmospheric pressure is lowered inside the chamber causing the lungs to expand and take in air. When the diaphragm is released the lungs deflate.Dimensions: 200mm x 200mm x 360mmProduct contains Latex.