Why are most IWC watches not chronometers?
The designation chronometer is registered and may only be applied if the movement of a watch has been tested by an independent inspection authority. In Switzerland this is the Swiss Official Chronometer Testing Institute or C.O.S.C. This inspection authority tests the movements submitted to it for their accuracy over a period of 15 days, involving testing for the first 10 days at room temperature and for the last 5 days at a range of different temperatures. If the measured deviations are found to lie within the set tolerances, a certificate is issued for the movement. IWC adjusts its watches according to its own internal criteria to closer tolerances than those of the C.O.S.C. Because we never have the performance results for our movements tested and verified by the C.O.S.C., we are not able to describe our watches as “Chronometers”. However, IWC has the movements of the most recent addition to its “Ingenieur” range of watches, Reference 3521, tested by the C.O.S.C. in order to be able
