THE OYSTER CASE

The symbol of waterproofness

The Oyster case constitutes an important milestone in the history of contemporary watchmaking. Invented by Rolex in 1926, it was the world's first waterproof case for a wristwatch thanks to its patented system of screwing down the bezel, case back and winding crown against the middle case. A symbol of robustness and waterproofness, this perfectly proportioned and elegant watch case is a superb blend of form and function, whether crafted in 904L steel, 18 ct gold or 950 platinum.

Oyster Case
waterproof watches

THE STRENGTH
OF A CONCEPT

Oyster Case

Today, thanks to the hermetic construction or their case, all Oyster watches are guaranteed waterproof to a depth of at least 100 metres (330 feet), and up to 3,900 metres (12,800 feet) for the Rolex Deepsea extreme divers' watch.

SOLID MIDDLE CASE
The Oyster’s middle case (the central section of the case) is stamped and machined out of a solid block of 904L steel, 18 ct gold or platinum. It is extremely robust and forms the backbone to which all the other parts of the case are securely fitted. Certain Professional models feature a crown guard on the side – these shoulders are stamped as an integral part of the middle case.

SCREW-DOWN CASE BACK, ROLEX FLUTING
The back of the Oyster case is hermetically screwed down against the middle case. The characteristic fluting on Oyster case backs, a legacy from the Oyster of 1926, fits into a special tool exclusive to authorized Rolex watchmakers, so only they can access the movement.

WINDING CROWN

Crowned with success

A little masterpiece of technical prowess, the winding crown of Rolex watches is made up of about 10 parts, and is screwed hermetically onto  the watch case. This is how Rolex, for the first time in the history of watchmaking, crafted a waterproof winding crown –– a secure interface between the protected, sealed world inside the watch and the harmful elements of the outside world.

Rolex Twinlock and Triplock winding crowns use two or three sealed zones to ensure watertight security akin to a submarine’s hatch.

Rolex winding crown
Oyster Case
Cyclops lens
cy • clops • lens
  1. A magnifying lens patented by Rolex in 1953 to enlarge the emblematic date of the Datejust.
  2. Named after the one-eyed giant of Greek mythology.
  3. A signature feature of Rolex watches, easily recognisable from a distance.
  4. Made of the same scratchproof sapphire as the crystal to which it is affixed.
  5. Featuring a double anti-reflective coating to ensure extra-clear legibility of the date.
  6. The Rolex Way.

The Bezel

Form and function

At Rolex, form and function are often closely intertwined. This is particularly true of the bezel, an essential component in the  strong visual identity of Oyster watches. Bezels in a wide variety of forms, fixed or rotatable, have been introduced over the years, offering new functions according to the watch type: diving time, second time-zone, 24-hour display, tachymeter scale, etc.

The fluted bezel

The fluted bezel

A Rolex signature

Originally, the fluting of the Oyster bezel  had a functional purpose: it served to screw the bezel onto the case helping to ensure the waterproofness of the watch. It was therefore identical to the fluting on the caseback, which was also screwed onto the case for waterproofness, using specific Rolex tools. Over time, the fluting became an  aesthetic element, a genuine Rolex signature feature. Today the fluted bezel is  a mark of distinction, always in gold.

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