Hamilton electric wristwatch, 1957.

Launched by the Hamilton Watch Company of Pennsylvania, United States on 3 January 1957, this was the world's first battery-powered wristwatch. A significant advance in the development of electric timekeeping, it took more than ten years to develop. The timekeeping was controlled by a conventional balance wheel, but kept in motion by electromagnets, rather than a main spring. The Hamilton electric watch was an instant success, making the need to wind watches by hand a thing of the past. Its popularity was also due to its modern styling - Hamilton employed designer Richard Arbib to produce a range of dramatic case styles to accompany the movement. These watches were in production until 1969, when they were replaced by superior quartz movement technology.