The markings under the coronet on a Rolex winding crown identify two things: which sealing system the crown uses, and what metal the crown is made from. A dash or one to two dots means a Twinlock crown. Three dots means a Triplock. Steel carries a dash on Twinlock and three equal dots on Triplock. Gold carries two dots, or three dots with a larger centre. Platinum carries a single dot, or three dots with a smaller centre.
That is the whole code in five sentences. Below is the full chart, the model-by-model reference, and the three situations where the marking on your crown will not say what you expect it to.
At EUROWATCH OC in Newport Beach we check the crown on every Rolex that comes through the door, whether it is arriving for sale or leaving with a buyer. It is a thirty-second read that tells a watchmaker more than most people realise.
What are the markings under the Rolex coronet?
Rolex stamps a small code into the face of the winding crown, directly beneath the five-point coronet logo. The code is watchmaker shorthand. It states the crown's sealing system and its metal without anyone having to open the case or pull a reference from the paperwork.
Three words matter here and they get used interchangeably, which causes most of the confusion:
- Coronet is the five-point crown logo. It appears on the dial, the crown, the clasp and the caseback.
- Crown is the button on the side of the case at 3 o'clock that winds the movement and sets the time. On an Oyster case it screws down against the tube.
- Tube is the threaded fitting mounted in the case that the crown screws into. Half the sealing happens in there.
So the markings sit on the crown, under the coronet. Ask a watchmaker about "the crown markings" and this is what they mean.
Rolex crown markings chart
Six combinations cover every modern Rolex.
| Marking under the coronet | Crown system | Crown metal |
|---|---|---|
| One horizontal dash or bar | Twinlock | Steel (Oystersteel) |
| Two dots, side by side | Twinlock | 18k gold: yellow, white or Everose |
| One dot, centred and alone | Twinlock | Platinum |
| Three dots, all the same size | Triplock | Steel (Oystersteel) |
| Three dots, centre one larger | Triplock | 18k gold: yellow, white or Everose |
| Three dots, centre one smaller | Triplock | Platinum |
Count the dots first. The count tells you the system. Then compare their sizes against each other, not against a photograph, because dot size only reads correctly in relation to the other dots on the same crown.
What is a Twinlock crown?
The Twinlock crown arrived in 1953 and seals the case at two points. One gasket sits inside the crown itself. A second sits inside the tube. Screw the crown home and both compress at once, which is where the name comes from.
Rolex fits it to the models that are water-resistant without being dive watches. Every Oyster case is rated to at least 100 metres, and a Twinlock crown handles that comfortably. It is also the slimmer of the two crowns, which matters on a dress case where a large Triplock would sit awkwardly.
Which Rolex models use a Twinlock crown?
- Datejust
- Day-Date
- Oyster Perpetual
- Explorer and Explorer II
- Sky-Dweller
- Air-King
- Milgauss
All of these carry a 100 metre rating. That figure belongs to the watch, not to the crown, which is a distinction worth holding onto for the section below.
What is a Triplock crown?
Rolex introduced the Triplock in 1970 on the Sea-Dweller. It adds a third sealed zone: two O-ring gaskets sit in the tube and the third sits inside the crown. It is also visibly larger than a Twinlock, which is often the first thing you notice before you count any dots.
The Submariner received it in 1977. The last hand-wound Daytonas, references 6263 and 6265, changed over during their production run, and every automatic Daytona since has used it. The ceramic-bezel GMT-Master II adopted it in 2007, replacing the Twinlock crown fitted to the aluminium-bezel generation before it.
Which Rolex models use a Triplock crown?
- Submariner and Submariner Date
- Sea-Dweller
- Deepsea
- Cosmograph Daytona
- GMT-Master II
- Yacht-Master
Twinlock vs Triplock: what actually differs
| Twinlock | Triplock | |
|---|---|---|
| Introduced | 1953 | 1970, on the Sea-Dweller |
| Sealed zones | Two | Three |
| Gasket placement | One in the crown, one in the tube | One in the crown, two in the tube |
| Crown size | Smaller | Noticeably larger |
| Marking | Dash, or one to two dots | Three dots |
| Fitted to | Datejust, Day-Date, Oyster Perpetual, Explorer, Sky-Dweller, Air-King, Milgauss | Submariner, Sea-Dweller, Deepsea, Daytona, GMT-Master II, Yacht-Master |
| Water resistance of the models it appears on | 100m | 100m on the Daytona and GMT-Master II, 300m on the Submariner, 1,220m on the Sea-Dweller, 3,900m on the Deepsea |
That last row is where most guides go wrong. You will read that "Twinlock is rated to 100 metres" or "Triplock is good for 300 metres" as though the crown carried its own rating. It does not. Rolex rates the finished watch, and the rating depends on the case, the caseback, the crystal, the gaskets and their condition. A Daytona and a Deepsea both use Triplock crowns and their ratings differ by 3,800 metres.
Rolex crown markings by model
Cross-reference your model against the marking you can see. Where a cell reads not produced, Rolex has not offered that model in that metal in the modern lineup.
| Model | Crown | Steel | 18k gold | Platinum |
|---|---|---|---|---|
| Rolex Submariner | Triplock | Three equal dots | Larger centre dot | Not produced |
| Rolex Sea-Dweller | Triplock | Three equal dots | Larger centre dot | Not produced |
| Rolex Deepsea | Triplock | Three equal dots | Larger centre dot | Not produced |
| Rolex Daytona | Triplock | Three equal dots | Larger centre dot | Smaller centre dot |
| Rolex GMT-Master II | Triplock | Three equal dots | Larger centre dot | Not produced |
| Rolex Yacht-Master | Triplock | Three equal dots | Larger centre dot | Not produced |
| Rolex Datejust | Twinlock | Dash | Two dots | Not produced |
| Rolex Day-Date | Twinlock | Not produced | Two dots | One dot |
| Rolex Oyster Perpetual | Twinlock | Dash | Not produced | Not produced |
| Rolex Explorer | Twinlock | Dash | Two dots | Not produced |
| Rolex Explorer II | Twinlock | Dash | Not produced | Not produced |
| Rolex Sky-Dweller | Twinlock | Dash | Two dots | Not produced |
| Rolex Air-King | Twinlock | Dash | Not produced | Not produced |
| Rolex Milgauss | Twinlock | Dash | Not produced | Not produced |
The Day-Date row is worth a second look. Rolex has never made a steel Day-Date, so a Day-Date crown showing a dash is either not a Day-Date or not wearing its original crown. Small details like that are why the crown gets checked early in an inspection. We keep the full range in stock across these references, and you can see current pieces in our Rolex watches for sale.
How to read the markings on your own Rolex
- Get the light right. These stamps are shallow. Hold the watch at an angle under a bright, directional light rather than flat under a ceiling lamp. A 10x loupe helps and a phone camera in macro usually does not, because the flash washes the relief out.
- Unscrew the crown and hold it steady. Turn it anticlockwise until it releases, then look straight down at the flat face. Screwed down, the marking often sits at an angle you cannot read.
- Count before you judge. One dash, one dot, two dots or three dots. The count settles the system, and it is the reliable part of the read.
- Compare dot sizes to each other. On a Triplock crown the whole question is whether the centre dot is bigger, smaller, or the same as the two beside it. Judge them against each other on that crown. Comparing to a photo of a different watch will mislead you, because crown diameters vary by model.
- Check it against the chart, then confirm elsewhere. Match the marking to your model above, then verify with the reference and serial. Our guide to Rolex serial numbers covers where to find them and what production year they point to.
If the marking looks faint or partly gone, the crown has probably been polished at some point. Polishing rounds the edges of a shallow stamp quickly, and a heavily polished crown can lose its dots entirely.
What the markings mean on a two-tone Rolex
The marking describes the crown, not the case. On a Rolesor Datejust in steel and yellow gold, Rolex fits a gold crown, so it reads two dots even though most of the case and bracelet are steel.
This trips people up constantly. Someone buys a two-tone Datejust, reads that two dots means gold, sees a mostly steel watch and assumes something is wrong. Nothing is wrong. Rolex matches the crown to the gold elements of the case, and the code reports the crown honestly.
The same logic runs the other way on older watches. On earlier Rolex models the code itself was different: a bar covered steel and yellow gold both, and two dots indicated white gold. If you are reading a vintage crown against a modern chart, that is the first thing to rule out.
Vintage Rolex crown markings: Brevet, the patent cross and Super Oyster
Before the Twinlock arrived in 1953, Rolex used a different set of marks entirely. Two turn up regularly on pre-1960s watches:
- The patent cross. A plus sign beneath the coronet, indicating a patented crown design. Rolex stopped using it after the Swiss government raised concerns that a cross could be read as a state endorsement.
- Brevet. The French word for patent, spelled out on the crown face instead of the cross.
There was also a short-lived experiment. In 1952 and 1953 Rolex produced "Super Oyster" crowns that did not screw down at all, relying on a spring-loaded seal instead. They were replaced quickly and they are a collector curiosity now.
The practical takeaway: a patent cross on a watch from the 1980s means the crown has been swapped. That is common on vintage pieces and it is not necessarily a problem, but it is a fact a buyer should know before money changes hands.
What crown markings cannot tell you
Four limits, and every one of them causes an argument at some point.
1. They do not confirm the case metal. Two-tone watches carry a gold crown on a largely steel case.
2. They do not survive polishing. A crown that has been polished a few times over forty years may show almost nothing.
3. They do not prove the watch is genuine. Counterfeiters copy dot patterns. It is not a difficult thing to fake.
4. They do not give you a water-resistance rating. That belongs to the model and to the condition of the gaskets. A 300 metre Submariner with a dried-out crown gasket is not water resistant to anything.
There is a fifth point that sits underneath all of these. Crowns are a service part. Rolex replaces them during routine servicing, and a correct replacement can still produce a marking that looks off against the chart if the wrong variant was fitted. A mismatch is a reason to ask questions, not a verdict.
Do Rolex crown markings prove a watch is real?
No. Crown markings are a useful early signal and nothing more. A counterfeit can reproduce a dot pattern, and a genuine Rolex fitted with a service crown can show a marking that does not match its reference.
Real verification looks at several things together: the reference and serial numbers and whether they agree with each other, the dial printing and lume, caseback and lug stamps, bracelet and clasp codes, the movement itself, and the micro-etched coronet at 6 o'clock on the crystal. Our full walkthrough of how to authenticate a Rolex goes through each of those in order.
For anything you are about to buy or sell, get it inspected properly. We offer watch authentication in Newport Beach with a multi-point inspection, and it takes very little time compared to what a mistake costs.
The other Rolex crown: the coronet logo
Search "Rolex crown" and half the results are about the winding crown and half are about the logo. The logo is properly called the coronet: five points, in use since the 1930s, and applied to the dial at 12 o'clock, the crown face, the clasp and the caseback.
One version matters for authentication. Since the early 2000s Rolex has laser-etched a tiny coronet into the sapphire crystal at 6 o'clock. It is nearly invisible without magnification and angled light, and it is difficult to replicate cleanly. Fakes tend to get it wrong by making it too visible, too deep, or slightly the wrong shape.
Collectors have also given nicknames to particular coronet printings on vintage dials. The "Bart Simpson" coronet, named for the shape of its points, and the "Frog Foot" are two of the better known. These are collector terms, not Rolex terminology, and they describe printing variations on specific dial batches rather than anything Rolex documented.
Frequently asked questions
What do the dots on a Rolex crown mean?
They identify the crown's sealing system and its metal. One or two dots or a dash means a Twinlock crown. Three dots means a Triplock. Within each system, the pattern also indicates whether the crown is steel, 18k gold or platinum.
What does a single dot on a Rolex crown mean?
A single centred dot means a platinum Twinlock crown. It does not mean a "single-lock" crown. Rolex has never made one. That misconception comes from assuming the dot count maps to the number of seals, which it does not.
What does the line under the Rolex crown mean?
A horizontal dash means a steel Twinlock crown on modern Rolex watches. On older models the same dash also appeared on yellow gold, so on a vintage piece it needs cross-checking against the reference.
Is a Triplock crown better than a Twinlock?
Neither is better. They are built for different jobs. Triplock adds a third sealed zone for models that need serious depth rating, and it is a physically larger crown. A Datejust does not need one, and fitting it would make the watch worse to wear.
Do all Rolex watches have a screw-down crown?
No. Every Oyster case model does, which is most of the catalogue. The Perpetual 1908 and the discontinued Cellini line are not Oyster cases, have push-pull crowns, and are rated to 50 metres rather than the 100 metre Oyster minimum.
Can a Rolex crown be replaced?
Yes. The crown and tube are serviceable parts and Rolex replaces them when the gaskets or threads wear. This is the usual explanation when a marking does not match the reference, particularly on a watch that has been serviced several times.
Why won't my Rolex crown screw down?
Usually cross-threading, debris in the threads, a worn gasket or a bent stem. Never force it. Press the crown gently against the case and turn anticlockwise first until you feel it seat, then turn clockwise. If it still resists, stop and have it looked at, because forcing a crown damages the tube and the tube is part of the case.
Does a two-tone Rolex have a gold crown?
Yes, on Rolesor models Rolex fits a gold crown, so it carries the gold marking of two dots on Twinlock or a larger centre dot on Triplock. The case and bracelet being mostly steel does not change the crown code.
What is the tiny crown at 6 o'clock on the crystal?
A micro-etched coronet, added by Rolex from the early 2000s as an anti-counterfeiting measure. It sits in the sapphire just above the rehaut at 6 o'clock and needs magnification and angled light to see.
Do crown markings affect a Rolex's value?
Only through originality. A crown that is correct for the reference supports the case that the watch is unmolested, which matters on vintage pieces. A replaced or incorrect crown is a talking point in a valuation rather than an automatic deduction.
Have your Rolex checked in Newport Beach
EUROWATCH OC inspects the crown, reference, serial and bracelet codes on every Rolex that comes through the showroom, whether it is arriving for valuation or leaving with a buyer. If you are buying, selling or simply want a second opinion on something you already own, bring it in.
EUROWATCH OC, 3388 Via Lido Ave, Newport Beach, CA 92663. Call 949-994-0114.
EUROWATCH OC is an independent luxury watch dealer. It is not an authorized Rolex retailer and has no affiliation with Rolex SA or Rolex USA. Rolex, Oyster, Oyster Perpetual, Twinlock, Triplock, Submariner, Sea-Dweller, Deepsea, Daytona, GMT-Master II, Yacht-Master, Datejust, Day-Date, Explorer, Sky-Dweller, Air-King and Milgauss are registered trademarks of Rolex SA, used here to describe the watches offered for sale.
