Chronometer/Master Chronometer
Specific sections/general information3
OMEGA watches with a chronometer-certified movement
A chronometer is a high-precision watch whose movement has been 
individually tested, for 15 days in 5 positions and at 3 temperatures, 
by a neutral official body (COSC) in accordance with the ISO 3159 
(NIHS 95-11) Standard. Each chronometer is unique, and identified by 
a number engraved on its movement.
COSC: Official Swiss Chronometer Testing Institute
NIHS: Swiss Watchmaking Industry Standard
Master Chronometer OMEGA certified watches
In addition to the COSC movement certification, Master Chronometer 
watches are individually tested at OMEGA for 10 days before they 
are delivered to the end customer. Test trials, based on a simulation 
of wear of the finished watch, aim to ensure the precision, resis
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tance to magnetic fields (1.5 tesla / 15,000 gauss), power reserve 
and water-resistance of Master Chronometer watches. The process, 
measurement equipment, and results obtained for each watch are 
certified by METAS.
METAS: Federal Institute of Metrology (Switzerland)
15,000 gauss
Specific sections/general information 3
Your OMEGA watch is designed to resist a magnetic field of 
15,000 gauss. This is an intensity higher than any to which it will be 
exposed in everyday use (for example, the magnet in a handbag clasp 
may attain 2,000 gauss). Not only will your watch not stop in the pre
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sence of a magnetic field, it will not even suffer any loss of accuracy 
after being exposed to such a field.