A tower clock is typically one, two, three, or four clocks as a set, located on an upper extension of a building. Many tower clocks are located on buildings but they can also be found on free-standing towers or structures, such as cell phone antennae towers. Tower Clocks are large, exterior clocks, with or without illumination. The clocks can be run by independent or central clock movements. Once common mechanical tower clock movements have been superseded by modern maintenance free electric clock movements with their associated electronic controllers.
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