The Wrigley Building’s clock tower. The giant two-story clock in the south tower features four dials, each 19 feet, 7 inches in diameter. Each dial has an hour hand that measures 6 feet, 4 inches and a minute hand that is 9 feet, 2 inches long. These clock hands were originally made of redwood, but were recently refashioned in aircraft-grade aluminum to increase their durability. Because of its multiple dials and prominent positioning, people coming from all directions use the clock to check the time.