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[Categories] Chronometer/accuracy [Answer] Chronometers are watches whose accuracy has been confirmed by a COSC (Contrôle Officiel Suisse des Chronomètres) testing centre. IWC adjusts its watches using its own in-house criteria. IWC, for example, does not tolerate a watch running slow, which is permissible in a chronometer test. Apart from this, the owner’s habits and lifestyle play a not unimportant role for a watch’s accuracy. Automatic movements behave differently with wearers who are physically very active than with people who lead quieter lives. Any divergence from the tolerances mentioned is not so much a question of function but is primarily one of adjustment and wearing habits. [Question] 
Why does IWC have no chronometers in its range?
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