Enlarged, 2X life-size heart shows exterior and interior views. Three easy-access flaps flip open for internal study. The chambers and valves are accurately reproduced to scale. The flexible chordae tendinae and cusps permit easy-to-see demonstrations of valve action. Includes attached sections of the trachea and esophagus. Mounted on a hardwood stand, this model measures 6" x 9" x 15". Teacher’s guide/answer key lists 45 structures that are permanently hand-coded on the model.