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By May 26, 2022October 14th, 2022Glossary - Rolex


Annual calendar system developed by Rolex. Its patented mechanism automatically differentiates between 30-day and 31-day months. This calendar feature, which equips the Sky-Dweller, requires only one date adjustment per year as February changes to March – February having only 28 or 29 days – and thus displays the correct date throughout the year.

Superlative Chronometer

The Superlative Chronometer certification, featuring quality standards that were redefined in 2015, is particular to Rolex. It now applies to a fully assembled watch, after casing the movement, and is a guarantee of superlative performance on the wrist in terms of precision, power reserve, waterproofness and self-winding efficiency. All Rolex watches are covered by the new Superlative Chronometer certification, a status symbolised by the Rolex green seal and coupled with an international five-year guarantee.


A silicon hairspring developed and manufactured by Rolex. Carrying several patents, the Syloxi hairspring is insensitive to magnetic fields and offers great stability when exposed to temperature fluctuations, as well as up to 10 times greater precision than a traditional hairspring in case of shocks. Its performance is based on novel solutions, including optimised geometry and an innovative design of the fixation systems.