What Does “Oyster” Mean on a Rolex Watch?

You’ve probably seen the words “Oyster Perpetual” on almost every Rolex watch you’ve encountered. But what does “Oyster” actually mean on a Rolex? And why is it “Perpetual?” Well, in a nutshell, Oyster refers to water resistance and Perpetual means automatic winding. A lot of Rolex technology, patents, and marketing went into making an Oyster Perpetual what it is today. In the following article, we’ll explore what exactly a Rolex Oyster is, and why there’s such significance in a watch being an Oyster Perpetual.

What is a Rolex Oyster?

“Oyster” is Rolex’s trademark for their water-resistant watch case (including the crown and caseback). In 1926, hardly 20 years since the company’s inception, Rolex launched its waterproof watch (as it was marketed at the time) named after the beloved bivalve mollusk.

If you remember picking up seashells as a kid and finding one still closed, or, if you like seafood and have struggled getting at the meal that lay before you – then the connection of the oyster to that of a water-resistant watch case should be clear. Nomenclature aside, three simple facts should be noted:

1. The Oyster case constituted a screwed-in (or screw-down) bezel, case-back, and crown which actually assured their real-world water resistance, just as advertised. Press-fit and snap-on bezels replaced the screwed-in kind, thus the early “3-piece” Oyster case was phased out by 1945 or so.
2. Rolex founder Hans Wilsdorf, marketing genius that he was, advertised his innovation for all it was worth via publicity stunts such as Mercedes Gleitze’s 1927 swim across the English Channel while wearing a Rolex Oyster on her neck. 
3. Rolex secured patent CH114948A (invented by Georges Perret and Paul Perregaux, no relation to Girard-Perregaux) for their water-resistant Oyster watches which solidified their pioneering position at the time. And Rolex introduced the Deepsea Challenge (capable of going to the deepest point in the ocean) in 2023 to emphasize that even today, few watch brands – if any – can rival Rolex in terms of water resistance.

What is a Rolex Oyster Perpetual?

Every Rolex Oyster with automatic winding is a Rolex Oyster Perpetual. While the Oyster case was a game changer, it wasn’t truly complete until it became the Oyster Perpetual in 1931. I’ll explain first that, in Rolex-speak, “Perpetual” simply means a mechanical watch movement with automatic winding. And this is not to be confused with a perpetual calendar, a concept that, though prevalent nowadays, was anything but commonplace in the first half of the 20^th century.

The thing to consider about a screw-down crown is that it’s a bummer to screw in and out constantly. Say, if you need to wind the watch daily – then you run the risk of eventually stripping or ruining the threads of the screw-down crown. This was one reason, incidentally, for the invention of the Panerai Luminor’s iconic crescent-shaped latching crown-guard mechanism.

In a true case of form following function, early Panerai watches (commissioned for use by the Italian Navy frogmen and made with Rolex Oyster cases) started getting equipped with this patented “Tight Seal Device” in 1955 to address water resistance issues caused by frequent winding of the screw-down crown. Budget constraints were presumably the reason they didn’t simply order automatic movements.

Wilsdorf in his brilliance had long foreseen the importance of automatic winding, and had been working towards a self-winding Rolex wristwatch as soon as the Oyster was released. While it took some experimenting, eventually, in 1931, the Rolex Oyster Perpetual was born. In essence, this is a model that is named after its two defining technological features – water resistance and automatic winding.

It not only stands on its own as the longest-running model in the history of Rolex and one of the oldest branded wristwatch models in general, surpassed by very few models from other brands (Cartier, interestingly, being one of them), but it also forms the core identity of the what has become characteristic of the brand – in the sense that nearly all the future icons in the Rolex lineup have built upon the Oyster Perpetual foundation. And it says so on their dial.

Was it the First Waterproof Watch?

No, it’s a bit of a Rolex myth that the Oyster was the world’s first waterproof watch. The Oyster probably was the world’s first daily-usable waterproof watch that didn’t use cork (because Rolex used rubber instead) and the Oyster Perpetual was the first automatic waterproof watch. But for a more thorough debunking of Rolex’s overall “first waterproof watch” claim, you can see Stan Czubernat’s book.

Regardless, the Oyster wasn’t even Rolex’s first waterproof watch – they made the cumbersome and primitive “Submarine” in 1922 – although it was their first truly practical one. And I will say that the Rolex Oyster does look more elegant than the waterproof Depollier watches that preceded it, for instance.

Do They All Have Screw-Down Crowns?

Every Rolex Oyster made since 1954 has a screw-down crown. For some reason, in 1952-1953, Rolex made some non-screw-down “Super Oyster” crowns that aren’t really so “super” after all. But aside from that anomaly, Oysters are all screw-down.

Is Every Rolex an Oyster Perpetual?

Most Rolexes – including all modern sports models – are Oyster Perpetuals, but there are exceptions.

• Neither Oyster nor Perpetual: Probably a vintage dress watch. Not the company’s forte, but they do exist, nonetheless.
• Perpetual, not Oyster: The current 1908 collection (like the 39mm Cellini collection that preceded it) is Perpetual (automatic) but not an Oyster. There are also a couple of dressy vintage Perpetual non-Oyster references, but they’re rare.
• Oyster, not Perpetual: A manual-wind waterproof model, like a 4-digit Daytona or an old entry-level Oyster. These haven’t been made since the late 1980’s.

Note that Rolex non-Oysters are by no means bad watches, and in fact I currently have my eye on a specific discontinued Cellini. But there’s no arguing that the dressier Rolex models have never appealed to such a wide audience or generated such demand as their Professional (sports) models.

So, while the next Rolex I buy personally might be neither an Oyster nor a Perpetual – you can be sure that’s just me wanting to be a contrarian. Today, and for quite nearly a century, being an Oyster Perpetual, that is a water-resistant self-winding watch, has been the defining feature of what makes a Rolex – a Rolex.