Only movements which meet the precision criteria established under ISO 3159 are granted an official chronometer certificate.

Movements are tested for 16 consecutive days according to a tests panel.

(Refer to enclosed tables)

• Every day, including Saturdays and Sundays, movements are measured and rewound.
• Based on these measurements, 7 eliminatory criteria are calculated.
• If and only if all these criteria are met, the movement is duly "chronometer-certified".

> Please refer to the table summing up these criteria and their degrees of tolerance.