"Due to their incredible height – an average of 15- to 18-feet – the blood vessels in giraffes’ lower legs are under great strain because of the weight of fluid pressing down on them. But despite the stress on their veins, giraffes never suffer from swelling or ulcers in their lower legs. [...] The giraffe’s tough, non-elastic skin works like the anti-gravity suit worn by astronauts, preventing the stagnation of blood in their lower extremities. That inspired scientists at 3M to create a compression system to help treat a painful human medical condition called venous leg ulcers, which are caused by uncontrolled high pressure in the veins of the lower leg. Venous leg ulcers are extremely common in the United States and affect between 500,000 to two million people."