all original and intact oversized late 1940's anatomical human heart instructional model comprised largely of molded plastic. the detailed human heart demonstration model is many times greater then the size of a human adult heart to clearly see and visually emphasize structural components. the brightly colored molded plastic anatomical model features heart chambers and valves with attached portions of trachea and esophagus to demonstrate their relationship to major vessels. any and all of the cardiac structures were meticulously hand-painted in small black numbers. the segmented, or more specifically, bisected large heart model was designed and fabricated by the denoyer-geppert co., chicago, il. the circumference measures approximately 27 inches with a height of 15 inches.