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By Glossary - Rolex


Screw-down winding crown with a triple waterproofness system developed by Rolex to enhance the water resistance of its divers’ watches, which is also now fitted on a number of Professional models. The Triplock system is identified by three dots (with sizes that differ depending on the material of the crown) below the Rolex emblem on the face of the winding crown. The Triplock system ensures waterproofness to a depth ranging from 100 to 3,900 metres (300 to 12,800 feet) depending on the case.


Screw-down winding crown with a double waterproofness system developed by Rolex. It ensures waterproofness to a depth of 100 metres (330 feet). Depending on the material of the crown, the Twinlock system is identified by one dot, two dots or a line below the Rolex emblem on the face of the winding crown.


By Glossary - 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.


By Glossary - Rolex

Ring Command

System of interaction between the case and movement developed and patented by Rolex for easy selection and adjustment of particular functions via a rotatable bezel and the winding crown. On the Yacht-Master II, it affords access to the programming function of this regatta chronograph’s mechanical countdown. On the Sky-Dweller, it allows easy selection of the functions to set: date, month, local time and reference time.


A term patented by Rolex in 1933, Rolesor refers to the combination of Oystersteel and 18 ct gold in its watches. Featured on Rolex models since the early 1930s, Rolesor is a true Rolex signature as well as a prominent pillar of the Oyster Perpetual collection. It is a harmonious combination of gold that is coveted for its lustre and nobility, and Oystersteel which reinforces strength and reliability.

Rolex Bracelet

The iconic band that comfortably secures a Rolex to the wrist. It comes in distinctive Oyster, Jubilee, Pearlmaster or President styles. Characterised by the solid-link construction for uncompromising strength, the patented Easylink system effortlessly extends the length for added comfort to achieve the perfect balance between elegance, function and reliability.

Rolex Glidelock

Bracelet extension system developed and patented by Rolex. Featuring a rack integrated into the clasp, it enables fine-increment adjustment of the bracelet length. The Rolex Glidelock equips the Oyster bracelet fitted on the Submariner, Submariner Date, Sea-Dweller and Rolex Deepsea divers’ watches, either with a fixed rack under the clasp cover or, for the Rolex Deepsea, a lift-up version that allows the bracelet to be adjusted without removing the watch from the wrist. The Yacht-Master 40, Yacht-Master 42 and Sky-Dweller models fitted with an Oysterflex bracelet, are also equipped with the Rolex Glidelock.


By Glossary - Rolex

Parachrom Hairspring

Patented in 1997, the Parachrom hairspring is developed and manufactured by Rolex from an alloy of niobium, zirconium and oxygen. It has the advantage of being insensitive to magnetic fields, being extremely stable when exposed to temperature fluctuations, as well as remaining up to 10 times more accurate than a traditional hairspring in case of shocks, thereby enhancing the movement’s chronometric performance. A surface treatment, applied since 2005, gives the Parachrom hairspring its blue colour and further improves the regularity of its pulsations over time.


An optimised shock absorber developed and patented by Rolex to protect the movement’s core components against sudden shocks. Compared to standard shock absorbers in watch movements, the Paraflex is up to 50 per cent more robust and resistant, enabling the movement to withstand demanding conditions and shocks, while ensuring uninterrupted chronometric precision.

Perpetual (Rotor)

Self-winding mechanism with a free rotor, developed and patented by Rolex in 1931. It consists of an oscillating weight that rotates in both directions under the impetus of the wearer’s wrist. In doing so, it winds the mainspring, which provides the movement with its source of energy.


By Glossary - Rolex

Oyster Case

The world’s first waterproof wristwatch case, pioneered by Rolex in 1926. It is a revolutionary system in which the case back and winding crown are hermetically screwed on to the case. The Oyster case is featured on every Oyster Perpetual model, guaranteeing waterproofness to a depth of 100 metres (330 feet).


Innovative bracelet developed and patented by Rolex. It combines the robustness and reliability of a metal bracelet with the flexibility, comfort and aesthetics of an elastomer strap. At its core lie two flexible metal blades – one for each section of the bracelet – overmoulded with high-performance black elastomer.


Oysterlock is a safety clasp system developed and patented by Rolex, designed to prevent accidental opening and ensure secure fastening of the bracelet. Housed inside a curved cover that seamlessly integrates with the bracelet, the Oysterlock comprises a click-down safety catch, a patented snap-fit lever, and a spring-loaded lever to prevent accidental opening.


Stainless steel alloy developed for Rolex, which offers an exceptional sheen. Oystersteel belongs to the 904L steel family – alloys whose excellent anti-corrosion properties are comparable to those of precious metals. In 1985, Rolex became the first watchmaking brand to use 904L stainless steel for cases of all its steel watches.


By Glossary - Rolex


A monobloc bezel or monobloc bezel insert, developed and patented by Rolex. Cerachrom is made of extremely hard, virtually scratchproof ceramics that use zirconia or alumina as a base material, featuring colours that are unaffected by ultraviolet rays. In addition, thanks to its chemical composition, the high-tech ceramic is inert and cannot corrode. For optimum legibility, the moulded graduations, inscriptions and numerals are coated with a thin layer of gold or platinum via Physical Vapour Deposition.


Luminescent display emitting a blue glow in dark conditions. Rolex’s watch hands, hour markers and other elements of the display are coated or filled with Chromalight, a high-performance luminescent material that is exclusive to the brand. Chromalight’s intensity and luminosity duration far outperform watchmaking standards.


Optimised Swiss lever escapement developed and patented by Rolex. The Chronergy escapement is developed based on extensive research that led to a new design for the pallet fork and escape wheel. Both redesigned components are manufactured from nickel-phosphorus, an alloy that renders them resistant to magnetic fields. Their innovative geometry offers the Chronergy escapement a 15 per cent improvement in energy efficiency compared to regular Swiss lever escapements, the standard in mechanical watches.


Concealed folding clasp designed and patented by Rolex, opened using a lever in the shape of a Rolex crown.

Cyclops Lens

The Cyclops lens, a name derived from the one-eyed giants in Greek mythology, was patented by Rolex in the early 1950s. Since 1953, it has magnified the date display in the aperture of many watches in the Oyster Perpetual collection for greatly enhanced legibility.


By Glossary - Rolex

Helium Escape Valve

Safety valve patented by Rolex in 1967 for divers’ watches designed for deep-sea diving. The helium escape valve allows excess pressure that builds up inside the watch case to be released during a diver’s decompression phase in a hyperbaric chamber. It features on the Rolex Sea-Dweller and Rolex Deepsea.


By Glossary - Rolex


Fold-out extension fitted on the majority of the Sea-Dweller and Rolex Deepsea divers’ watches. It allows the Oyster bracelet to be lengthened by approximately 26 mm for wear over a diving suit.


By Glossary - Rolex


Rapid comfort extension link developed by Rolex that allows the length of the watch bracelet to be adjusted easily. Opening or folding back the link allows the wearer to extend or shorten the bracelet by approximately 5 mm.

Everose Gold

An exclusive 18 ct pink gold alloy, developed and patented by Rolex, and produced in its own foundry. The composition of the alloy lends it a unique colour – a pink hue with an extraordinary sheen unlike any other that lasts for generations.


By Glossary - Tudor


Tudor’s proprietary rapid bracelet adjustment system, the T-Fit lets the wearer adjust the bracelet’s length in five positions of up to 8mm in total, without the need for tools. A recent innovation, the T-Fit debuted in the new Black Bay Fifty-Eight Bronze.