What is COSC certification and how does it impact my watch's accuracy?Updated 8 days ago

All of our collections, with the exception of the Parade, are certified by the COSC (Contrôle Officiel Suisse des Chronomètres).

What is the COSC?Founded in 1973, the COSC is an independent, non-profit organization recognized as a public interest body. Its mission is to test Swiss movements with absolute intransigence to award them the official title of "Chronometer." Only 6% of exported Swiss watches obtain this label, a true distinction of the watchmaking elite.

Extreme testing for total reliabilityEach movement in our watches undergoes a series of tests for 15 consecutive days. To obtain certification, the movement is tested in:

• 5 different positions (3 o'clock, 6 o'clock, 9 o'clock, dial up, dial down);
• 3 distinct temperatures (8°C, 23°C, and 38°C).In total, 7 eliminatory criteria are analyzed, the most famous being the average daily rate. To be certified, the average daily rate of a mechanical movement must strictly fall between -4 and +6 seconds per day.

The SERICA commitment: Beyond the standardThe COSC label certifies the movement alone (not yet cased). At SERICA, we go further to guarantee real-world performance on your wrist:

• Soprod COSC Movements: We have chosen to collaborate with the Soprod manufacture to integrate the M100 calibers (for our 6190, 6190 M.S.L., and 5303 references) and C125 (for our ref. 8315), both meeting these standards.
• Additional internal tests: Once the watch is assembled in our workshop, we perform a second rate check in 6 positions on a calibrated measuring device. We thus ensure that every delivered watch statically respects chronometric tolerances.

Can I check the accuracy of my watch myself?It is important to note that COSC certification tests are carried out under extremely strict laboratory conditions. Reproducing these results at home is complex because daily wear exposes the watch to variables (wrist movements, body temperature variations, light shocks) that differ from the static conditions of the tests. You can find the official measurement methods here: [https://www.cosc.swiss/notre-certification/methodes-de-mesure]

Watchmaker's note: Please note that external factors such as violent shocks, intense magnetic fields, or insufficient winding can influence the rate of your watch, even if certified. If in doubt, consult our article on accuracy diagnosis.