Contrôle Officiel Suisse des Chronomètres (COSC) is the largest Swiss independent testing facility for watch movements. Founded in 1973, this non-profit foundation aims to guarantee the precision of Swiss watches through a neutral, independent, and rigorous method. Watches with movements that passed the tests can be called “COSC-certified chronometers,” accurate to within -4/+6 seconds per […]
Visit A Closer Look At COSC’s New Excellence Chronometer Certification to read the full article.
