2654-stage cross-section of an artery demonstrating atherosclerosis in which the narrowing of the artery is due to a build up of fatty tissue (cholesterol) and plaque. 4-stages: normal artery, fatty streak, fibrous plaque, and blockage. The stages cause a decrease in blood flow, which can lead to a blood clot or thrombus. All stages rotate on hinge pin. Model Size: (4) 1-3/8" dia. x 7/8" x 3-1/2" Card Size: 6-1/2" x 5-1/4"