The European Chronometer Official Association believed that a chronometer rated watch had to be independently tested to be awarded that designation. Seiko watches were not independently tested so therefore they could not be chronometers. The ECOA did what irritated watchmakers do, they wrote a stern letter to Seiko requesting that the designation of Chronometer on Grand and King Seiko watches stop. Seiko obliged and ceased using chronometer on their watches. In response, the Japanese Chronometer Authorization Association was started in 1968 as an independent group to test timepieces to chronometer standards. The Association was short-lived: due to the rise of quartz watches, it closed in 1983.
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