Eterna is a luxury watch manufacturer headquartered in Grenchen, Switzerland. In 1851 it was established as a watchmaker training school. In 1932 Eterna established a movement company named ETA . ETA came to offer movement to Eterna and Swiss watch companies. In 1948, Eterna developed the automatic movement: Eterna-matic. By arranging five ball bearings, it is possible to increase the efficiency of the movement, to minimize the friction and resistance to wear of the spring bringing innovation in the history of the self wound timepiece. In 1948 a design imitating five bearings was adopted for the brand logo. The average sales price for Eterna is ฿49,155.