Rolex watches have come to represent a coupling of luxury and technological innovation. Rather than having to delicately handle and only occasionally wear a Rolex watch, Rolex has designed their product to be strong and durable, while maintaining that level of luxury that has come to be expected. Perhaps more than anything else, the unassailable reputation of Rolex watches rests on their ability to withstand the extremes. The brand’s products have truly been to the highest, lowest, hottest, and coldest places on Earth, handling with ease the most hostile environments the planet can offer. And key to much of their success can be attributed to an invention dreamt up all the way back in 1926: the Oyster case.
This relatively simple innovation, one which has gone largely unchanged for the last 90+ years, did more than anything before or since to popularize the wristwatch. Beyond even that though, it has also formed the backbone for almost everything Rolex has created since – and solved one of the main problems facing any mechanical watchmaker: water resistance.
Table of Contents:
- 1 The Waterproof Oyster Case
- 2 Waterproof or Water Resistant?
- 3 The Different Water Resistance Scales
- 4 The 5 Most Common Water Resistance Ratings
- 5 Rolex Watches and Their Water Resistance Rating
- 6 A Quick Look at Crowns
- 7 What Can Impact Water Resistance?
- 8 Water Got Into My Rolex. What Should I Do?
- 9 Final Notes on Water Resistance and Rolex Watches
The Waterproof Oyster Case
Before the Oyster case’s introduction, pocket watches were very much the only timepiece men used. Not so much for their practicality, but for the level of protection they afforded. Dirt, dust and moisture have always been among the biggest enemies of watch movements, and so keeping a pocket watch tucked away inside the wearer’s clothing when not in use helped safeguard its delicate internal components.
However, the usefulness of a model that could be worn on the arm was established during wartime, but the first examples proved relatively fragile. They were far more exposed to the elements than pocket watches and the earliest pieces allowed too much everyday detritus to enter the case and damage the caliber.
With the arrival of the Oyster, the brainchild of Rolex founder, Hans Wilsdorf, all of that was to change. Not only did the system of screwing the bezel, case back and crown against the middle case form an impenetrable barrier against the usual debris, it was so effective that it also provided a level of waterproofing never seen before.
Not one to shy away from promotion and advertising, Wilsdorf capitalized on this aspect of his timepieces in a series of marketing stunts. The most famous remains persuading a young British swimmer, Mercedes Gleitze to wear one of his Oyster models on a lanyard around her neck as she attempted to be the first person to swim across the English Channel in 1927. After 10-hours of being submerged in the icy waters, the watch came up still ticking.
The basic formula has been built upon and updated over the subsequent generations, until we reach today’s situation where all but the Cellini range of dress models in Rolex’s catalog benefit from at least 100m of water resistance. It all perfectly encapsulates the company’s original adage of building watches which are at once exceptionally handsome and stylish yet still resilient enough to be worn everyday.
Will any of these models ever be taken to 100m underwater? No, but a high water resistance factor isn’t just an indication of how deep a watch can be submerged, but is a testament to the robustness of the engineering as a whole. It is to demonstrate the prowess behind the manufacturing and give the wearer the peace of mind that they are unlikely to encounter anything that will seriously test the integrity of their watch.
Waterproof or Water Resistant?
If you research enough into the finer workings of mechanical watches, and particularly if you are interested in dive models, you will come across the terms ‘waterproof’ and ‘water resistant’ used interchangeably. They are not, however, the same thing.
Calling a watch waterproof suggests that it can never allow water to seep inside under any circumstances. This is, of course, impossible to claim. If you leave anything immersed long enough, it eventually will become compromised.
All watches are made up of a number of parts that have to fit together. Wherever those components meet becomes a potential weak spot that can hypothetically allow moisture to intrude, be it the sapphire crystal, the case back or especially the winding crown.
For that reason, the word ‘waterproof’ was banned by the FTC in the 1960s where it applied to watches and was replaced with the more accurate ‘water resistant.’
So what’s the difference?
Simply put, water resistant watches carry a rating which essentially certifies to what depth they will keep the water out, under ideal conditions. Every one of Rolex’s Oyster models is water resistant to at least 100m. The brand’s trio of dive watches – the Submariner, the Sea-Dweller and the Deepsea improve upon that considerably, coming in at 300m, 1,220m and 3,900m respectively.
So, true waterproofness can’t be guaranteed but, in the case of Rolex, it is worth noting that in 2014, one hapless vacationer lost his Submariner to the frigid Pacific Ocean during a fishing trip off the coast of British Columbia. It was found by a dredging company 14-months later, having lain at a depth of 100m all that time. A few turns of the crown (and removal of the barnacle from its bezel) and the watch started ticking away again.
No watch can truly be considered waterproof, but a Rolex dive watch comes about as close as anyone can realistically expect.
The Different Water Resistance Scales
Depending on the manufacturer, you will see a watch’s water resistance noted in one of three ways.
- Meters
- ATM
- Bar
Meters is the most common, usually denoted by the letter ‘M’ in either lower or upper case and obviously relating to the actual depth the watch can be taken. This is the system you will see on Rolex models, with the corresponding depth in feet next to it. So 100m equals 330ft.
ATM stands for ‘atmospheres’ and is a unit of pressure. 1 ATM is, as near as makes no difference, the same pressure as would be experienced at 10m. 10 ATM is the same as 100m, or 330ft.
Bar is another widely used measurement of pressure, only rarely seen on watches but fairly common when talking about filling Scuba tanks. 1 Bar is more or less the same as 1 ATM.
What Does Each Water Resistant Rating Mean?
If you are interested in diving as a sport you might sometimes wonder why a watch needs to be water resistant to 100m, let alone the fearsome ratings that the likes of the Rolex Sea-Dweller or Deepsea carry.
The maximum depth recommended by most organizations for recreational Scuba is less than 40m when diving with air, and even the current world record is standing at a little over 300m. So, very few people are going to be able or qualified to take any Rolex watch past its indicated rating in theory. But again, it is all about pressure. If you were to somehow dive to 100m and experience some further increase in pressure, there is a chance that water would likely breach the case and cause damage.
All watches are originally certified under strict laboratory conditions, using static (i.e. not moving) pressure and they are brand-new at the time of testing. Real world conditions can vary from a laboratory environment, and as components age (particularly gaskets) water resistance can become compromised. So what activities can you do wearing watches with the various depth ratings their manufacturers issue?
The 5 Most Common Water Resistance Ratings
Most watch manufacturers stick to the same five water resistance ratings, although you will sometimes see other values listed for certain models. With that in mind, here are the most common depth ratings that you are likely to en counter.
30m (100ft, 3 Bar, 3 ATM)
The lowest depth rating and the one you would expect every watch to have. It should be able to withstand the rain and standard hand-washing, but not much beyond that. Incidental contact with moisture is fine, but it is not advisable to take a watch with a 30m water-resistance rating swimming.
50m (165ft, 5 Bar, 5 ATM)
Still a very low resistance, but you should be okay for swimming if not too vigorous. Avoid any kind of high-impact water-sports, such as jet skiing or just diving into the pool. While a watch with a 50m depth rating should be fine for light swimming, it is not suitable for Scuba.
100m (330ft, 10 Bar, 10 ATM)
A good level of resilience which will keep the watch protected in virtually all everyday situations. Fine for swimming and snorkeling, but still not ideal for anything with dynamic pressure changes like high board diving or Scuba. While a watch with a 100m water-resistance rating can be used for Scuba diving (assuming it has fresh gaskets), most watches that were designed for Scuba will offer higher depth ratings.
200m (660ft, 20 Bar, 20 ATM)
The minimum level required for Scuba diving. A watch with a 200m depth rating is more than protected against day-to-day moisture contact, and in addition to Scuba, watches with 200m water-resistance ratings can also be worn during high-impact water-sports.
300m and above (1,000ft, 30 Bar, 30 ATM)
Any watch with 300m or more of water resistance can be worn for all water-sports as well as deeper and more prolonged diving activities. With the exception of saturation diving – an elite and highly specialized form of commercial diving where divers spend prolonged period in dry chambers, breathing different gas mixtures – a 300m depth rating is more than adequate for professional Scuba diving.
Rolex Watches and Their Water Resistance Rating
So, if those are the grades, how does the Rolex catalog measure up?
Below, we list each collection and their water resistance.
Rolex Cellini
Rolex’s family of out-and-out dress watches.
Case Size: 39mm.
Materials: Available only in 18k gold
Water Resistance: 50m
Click here to learn more about the history of the Rolex Cellini.
Rolex Datejust
Rolex’s bestselling model of all time and the perfect everyday watch.
Case Size: 28mm (Lady-Datejust), 31mm, 36mm, and 41mm.
Materials: Available in Oystersteel, Rolesor (two-tone), or 18k gold
Water Resistance: 100m/330ft
Click here to for the full history of the Rolex Datejust.
Rolex Day-Date
Sometimes known as the President or Presidential, the Day-Date remains Rolex’s flagship creation.
Case Size: 36mm, 40mm.
Materials: Available in 18k gold or platinum
Water Resistance: 100m/330ft
Click here to discover the nicknames and defining elements of the Rolex Day-Date.
Rolex Sky-Dweller
Rolex’s most recent new arrival and their first annual calendar-equipped watch.
Case Size: 42mm.
Materials: Available in Oystersteel (with white gold bezel), Rolesor (two-tone), or 18k gold
Water Resistance: 100m/330ft
Click here to learn how to set the annual calendar on the Rolex Sky-Dweller.
Rolex Oyster Perpetual
Rolex’s least expensive and most straightforward range of watches.
Case Size: 26mm, 31mm, 34mm, 36mm, 39mm.
Materials: Available in Oystersteel only
Water Resistance: 100m/330ft
Click here to learn more about the Rolex Oyster Perpetual.
Rolex Air-King
A simple, time-only model that can trace its roots back to the Second World War.
Case Size: 40mm.
Materials: Available in Oystersteel only
Water Resistance: 100m/330ft
Click here for the complete history of the Rolex Air-King.
Rolex Milgauss
The scientists’ watch, a model originally developed to resist strong magnetic fields.
Case Size: 40mm.
Materials: Available in Oystersteel only
Water Resistance: 100m/330ft
Click here for the full history of the Rolex Milgauss.
Rolex Explorer
Rolex’s first sports watch, the Explorer was created to celebrate the first successful ascent of Everest.
Case Size: 39mm.
Materials: Available in Oystersteel only
Water Resistance: 100m/330ft
Click here for the top 3 things to know before buying a Rolex Explorer.
Rolex Explorer II
A handsome dual time zone watch, the Explorer II is worn by many of the world’s adventurers.
Case Size: 42mm.
Materials: Available in Oystersteel only
Water Resistance: 100m/330ft
Click here to learn the difference between the original Explorer and the Rolex Explorer II.
Rolex Yacht-Master*
A lavish, nautically-flavored watch, the Yacht-Master is a more luxurious take on the Submariner
Case Size: 37mm, 40mm, 42mm.
Materials: Available in Rolesium (steel and platinum), Rolesor (two-tone), and 18k gold.
Water Resistance: 100m/ 330ft
Click here for the full history of the Rolex Yacht-Master.
Rolex Yacht-Master II*
A highly advanced model built for regattas, the Yacht-Master II features a programmable countdown timer.
Case Size: 44mm.
Materials: Available in Oystersteel, Rolesor (two-tone), white gold (with platinum bezel) and 18k yellow gold
Water Resistance: 100m/330ft
Click here to learn how to set the regatta timer on the Rolex Yacht-Master II.
Rolex GMT-Master II*
The legendary GMT watch and one of the most highly sought after models in the brand’s contemporary collection.
Case Size: 40mm.
Materials: Available in Oystersteel, Rolesor (two-tone), and 18k gold
Water Resistance: 100m/330ft
Click here for the complete history of the Rolex GMT-Master.
Rolex Daytona*
Built for the world of racing and quite possibly the most famous chronograph watch ever made.
Case Size: 40mm.
Materials: Available in Oystersteel, Rolesor (two-tone), 18k gold, and platinum
Water Resistance: 100m/330ft
Click here to learn more about the history of the Rolex Daytona.
Rolex Submariner*
The first dive watch to be water resistant to 100m and an icon against which all others are measured.
Case Size: 40mm.
Materials: Available in Oystersteel, Rolesor (two-tone), and 18k gold
Water Resistance: 300m/1,000ft
Click here for the full history of the Rolex Submariner.
Rolex Sea-Dweller*
Featuring a helium escape valve and built to withstand the crushing depths of saturation divers.
Case Size: 43mm.
Materials: Available in Oystersteel and Rolesor (two-tone)
Water Resistance: 1,220/4,000ft
Click here to learn more about the very first Rolex Sea-Dweller.
Rolex Deepsea Sea-Dweller*
Basically bombproof, the Deepsea is Rolex’s most imposing watch and one which could survive just about anything.
Case Size: 44mm.
Materials: Available in Oystersteel only
Water Resistance: 3,900m/12,800ft
A Quick Look at Crowns
Vital to the success of the Rolex Oyster case and its ability to keep water away from the watch’s internal parts is the security of the winding crown. Traditionally, the crown has always been the ‘Achilles Heel’ of watch design, an easy point of entry for moisture and all sorts of other junk you don’t want anywhere near a delicate movement.
The early examples of the Oyster case featured a patented screw down winding crown arrangement, fitted with a metal gasket that fastened securely into a tube in the center watch case to form a watertight seal. When the first Submariner was made in 1953, that system had to be bolstered to withstand the extra pressures, and so Rolex devised the Twinlock crown, with a second gasket system inside the tube to create two sealed zones. The O-rings were also made from a synthetic material to form a stronger barrier.
In 1970, with the introduction of the Sea-Dweller, Rolex beefed up their winding crowns again and brought out the Triplock, with its (you guessed it) a new gasket arrangement that created three sealed zones to prevent moisture ingress. This time, two are in the case tube and the third remains under the crown itself.
As you might imagine, Rolex’s trio of dedicated divers use the Triplock crown to ensure their incredible water resistance, but a number of other watches in the catalog do as well. The watches from our list above shown with an *asterisk (the two Yacht-Masters, the GMT-Master II, and the Daytona) are all fitted with a Triplock crown, while still only being rated to 100m. In their case, the decision to include Triplock crowns could be partially due an aesthetic choice. The Triplock crown is bigger than the Twinlock and is more in proportion with the rest of the piece.
What Can Impact Water Resistance?
As we have stressed, your watch’s water resistance rating applies only under certain conditions. You can think of it as the fuel economy figures car manufacturers quote on their brand new models. They will have been tested in tightly controlled environments to ensure their maximum gas mileage, something it is very difficult to replicate in everyday life.
It is the same with watches, and many of the things that affect a car’s performance apply here too. Below, we outline what factors can reduce the effective water resistance.
Age
Again going back to our car analogy, you wouldn’t expect a 10 or 20-year old model to return the same mileage as one just off the line. In the case of a vintage watch, it is usually safer (and cheaper) to assume they no longer hold the same sort of water resistance as they did when they were new.
Over time, their seals and gaskets lose their pliability and so their ability to form a tight seal. That’s why it is vital to have any watch, and particularly older models, serviced regularly – and we will cover that more in-depth in a minute.
Heat
Tempting though it may be, wearing your Rolex in the shower or hot tub is not advisable. Obviously its not the depth here that’s the problem, but rather the heat. Extreme temperature inversion, as you would experience walking into a sauna or jumping into a Jacuzzi, can hasten the deterioration of your watch’s seals.
Although Rolex use high tech fluoropolymers for their gaskets, which are especially resistant to corrosion and chemicals, as well as heat and cold, no material can be 100% guaranteed not to degrade or lose its shape eventually. Additionally, soap suds can also reduce the surface tension of the seals, and can also potentially damage the exterior finish of the watch too.
Aftermarket Parts and Accessories
This one really stands to reason. The Rolex manufacturing facilities are among the most cutting-edge industrial plants in the world, with countless millions of Swiss Francs poured into making sure every component made there is perfect. And, crucially, fits together with all the other parts to within tolerances measured in microns.
It is only this attention to detail, along with the extreme testing each watch is subjected to that allows the brand to make their claims about their performance. When you start replacing various elements of a Rolex with third party or aftermarket alternatives, there is a real risk of reducing the watch’s water resistance.
The Crown
Possibly the most common cause for a Rolex getting water damage is forgetting to screw the crown back in after winding or setting the watch – and unfortunately it is something easily done. Any horology nerd who tells you they haven’t been guilty of it at least once is probably lying.
If you’re lucky, you’ll notice before any damage is done, and with the Twinlock and Triplock systems, Rolex watches are theoretically water resistant even with the crown left out. However, combine an unscrewed crown with any of the other factors such as old seals, those affected by heat, or even just incidental motion of the open crown, and it is a recipe for disaster. This is just one of those things you will have to train your brain to remember, hopefully before you land yourself with a hefty repair bill.
Servicing
The number one best way to safeguard your watch’s water resistance will always be to stick to a regular servicing schedule. So, how regular is regular? That depends.
Since 2015, Rolex recommends 10-years between maintenance appointments, which is a massive gap and the longest in the industry. It is testament to just how confident the brand is in their engineering. Each new watch also gets a five-year warranty from date of purchase when it is first sold, but this does exclude user error.
It pays to remember the warranty applies to what Rolex calls ‘real life’ usage. If you subject the watch to an especially hard time, and particularly if it gets heavily knocked (something which can damage an internal gasket with no outward sign), then upping the frequency of service inspections is very much encouraged. Additionally, older watches can require more looking after. Vintage pieces will benefit from a service at least every five to seven years.
Whatever the age of your model, it is worthwhile having it at least pressure checked every year. This is a simple and inexpensive service most repair facilities offer, which will test the integrity of the watch’s seals so that you can replace any that are necessary.
Water Got Into My Rolex. What Should I Do?
Sometimes, it doesn’t matter how careful you are, the horology gods aren’t smiling on you and the worst can happen. If you get water inside your watch, it is likely the first you will know about it will be a slight condensation or fogging of the crystal. There might be other clues as well, such as the luminescence losing its glow or the hands stuttering or stopping entirely.
Once you’ve noticed any of these signs, time is of the essence. Salt water corrodes faster than fresh water, but whichever has found its way inside, it has the potential to do some real harm if not taken care of quickly. A watch caliber is made up of some extremely delicate parts and even the tiniest hint of rust caused by water damage will render them pretty well unserviceable.
What you do next depends on how long you think the water has been inside and how much there might be. If you believe it is just a small amount and it has only been there for a short time (say, a day or two) you may get away with trying to dry the watch out yourself. Leave it face up in a warm place; not too hot, as that can cause more problems. Alternatively, you could submerge the watch in some kind of desiccant, such as dry, uncooked rice or pure silica gel cat litter (preferably unused). These could well help to wick the moisture away from the most susceptible components, but this also does run the risk of getting debris into the movement if you are not careful.
All of that being said, we would always advocate a trip to your local watchmaker as soon as possible, regardless of how bad you think the water ingress might be. From the outside, it is impossible to tell just how much has infiltrated the case. Getting your piece to a service center as soon as possible could well be the difference between having to stump up for a once-over and a few replacement gears, or being served with a huge repair bill.
A professional watchmaker will be able to strip your model down, dry out and clean each part – of which there are likely to be at least 100 – and then properly reassemble it. While it won’t be the cheapest day out, it can be a small price to pay to go home with a working Rolex.
Final Notes on Water Resistance and Rolex Watches
For many people, Rolex really is the last word in watches designed to stand up to anything. That prominence hasn’t come about by chance, but rather as the end result of more than a century of tireless innovation, research and testing. Within the luxury mechanical watch sector, you will be hard pressed to find any other brand that can compete with Rolex, especially in terms of water resistance.
As we’ve seen, a water resistant watch isn’t ‘waterproof’ in much the same way that stainless steel isn’t stain proof. Not looked after properly, moisture or dirt will be able to get inside your Rolex regardless, and this is specially true if you neglect routine maintenance long beyond your watch’s recommended service interval.
However, thanks to the brand’s reputation for over engineering, along with generations spent perfecting manufacturing techniques, Rolex watches still make the ideal lifelong companion in just about any environment.
One of these technological innovations is a high resistance to water pressure. Through years of tried and tested models, Rolex is able to claim that all of their watches are waterproof, up to a certain amount of water pressure. Some are specially designed to be used by deep sea divers and can remain water resistant up to 1000 meters (3,281 ft). Despite this amazing feat, Rolex continues to develop new technologies and improve their watch’s water and pressure resistance. On 26 March 2012, the DSV Deepsea Challenger carried a Rolex Oyster Perpetual Date Sea-Dweller Deepsea Challenge prototype diving watch to a depth of 10,898.4 meters (35,756 ft). The watch resisted the water pressure and continued to perform with Rolex’s distinct precision. This is the deepest ocean depth anyone has explored, and a Rolex was there. However, the majority of Rolex watches can only maintain water resistance up to 300 meters.
How does this amazing technology work? Rolex’s patented Oyster case is one of the most famous features of Rolex watches. Invented by Rolex in 1926, the Oyster case is the world’s first waterproof case for a wristwatch. It works by utilizing a system of screwing down the bezel, case back and winding crown against the middle case. This forms a completely closed and impenetrable case, resembling that of an Oyster shell. This impenetrable case provides a safe and dry environment for Rolex’s high-precision Perpetual movement, keeping out an assortment of elements from water to dust to pressure.
While it may be water-resistant, there are still many watery places a Rolex watch should not go. For example, hot tubs and showers are tempting places to take a Rolex, as they are not deep, thus offer not threat to the watch. However, the heat of the water in a hot tub or shower could cause major damage to the watch. Rather than worrying about water penetrating the case, one should be concerned about a gasket losing its shape, thus allowing water to enter the watch. Soap-suds can also cause damage, reducing the surface tension of the rubber gaskets in the watch, allows water to get in. Soap could also potentially harm the exterior finish of the watch. Thus, wearing of a Rolex in hot tubs and showers should be avoided. If a slight or moderate fog appears under the watch’s crystal, the interior of the watch has been penetrated. To hopefully stop the damage, pull the crown to stop the watch’s movement. As soon as possible, take the watch to a certified Rolex dealer for assessment.
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you buy Tudor watches? I have an older model with Rolex case crystal bracelet and crown, all marked with
“Rolex” or the Rolex symbol on the crown. Stainless steel with gold plating on bracelet and case.
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Thank you so much for the tutorials! Very informative. Keep up the excellent work!
Dear Paul and the Bob’s team,
I plan to buy my next Rolex with you. There is so much fluff, pop up ads, regurgitated articles and in fact disinformation online, but not at Bob’s. How refreshing to get the facts. I’m an Air King guy, why because my last name is King. I bought my first two in Chicago, my hometown. Might you indulge me with a Q? While the 100M is NOW the standard, has it always been or what year did it become (at least for my model)? Thanks! cKs
Several decades ago, most Rolex watches outside of its dive watch collections featured 50m depth ratings, but that has since been updated to 100m across all models (excluding the Cellini series). The first Rolex Oyster Perpetual Air-King reference (the ref. 5500) had a 50m depth rating when it appeared in 1958, and by the time the second generation arrived in 1989, the Air-King had been updated to have a 100m depth rating. There is a chance that the Air-King 5500 might have been marketed with an updated depth rating near the end of its production simply due to how long it remained a part of Rolex’s catalog, but the actual design and structure of the watch did not change at all.