As one of the world’s most popular luxury watches, it should come as no surprise that the Rolex Submariner is also one of the most frequently “faked.”

From low-budget forgeries to high-end fakes that are practically indistinguishable from the genuine article, there’s a whole ecosystem of fake Submariners that can fool even some of the most distinguished Rolex aficionados.

If you’re buying from an Authorized Dealer (AD) or other major outlet, you’ll often get a certificate of authenticity or even branded paperwork to help put you at ease. But if you’re buying on the gray market, or purchasing a used Rolex from a private seller, the issue of authenticity becomes even more of a question.

So when you’re spending a small fortune on your new watch (one that will ideally last a lifetime), you want to know you’re getting the genuine article. How can you be sure?

Fortunately, there are a few “dead giveaways” that even a novice can notice

Dead Giveaway #1: Quality of Watch & Engraving

Rolex is more than just a name. It’s an obsession with quality.

From the world-class 904L steel and Rolex-made alloys to the in-house movements and precision craftsmanship, everything about a Rolex watch is made with a dedication to precision and perfection. So if something looks a little off, you should definitely take notice.

Specifically, take a look at the stamping of the serial and model number. The numbers should be perfectly marked, edged deep into the case and glowing like a diamond cut. If they look more like an acid-etched engraving, you’re probably looking at a fake.

Dead Giveaway #2: Dial Quality & Cyclops

If a Rolex dial had smudged or blotchy letters, it would’ve never left the factory. This is one of the first things most trained eyes will notice about a fake Submariner.

Sometimes, more often with Datejusts, a servicing or dial repainting can lead to small smudging, but even these should be well-documented by the seller. If they’re not, you should probably be on high alert.

Likewise with the “cyclops” magnifier. This is one of the most iconic parts of the modern Rolex, with a raised profile that magnifies the date 2.5x for easier reading. If it’s not the right size, or if it doesn’t sufficiently magnify the date, you’re probably looking at a fake.

Dead Giveaway #3: Exhibition Casebacks & Etching

Aside from a few particular vintage specimens, true Rolex Submariners will never have exhibition or etched casebacks. With the exception of a few Lady Datejust models, some Rolex Sea Dwellers, COMEX Submariners and military watches, Rolex casebacks should be plain stainless steel.

Dead Giveaway #4: Micro-Etched Crowns

Arguably one of the most fascinating ways that Rolex has made their watches counterfeit-proof is the micro-etched crown found on the surface of the crystal.

Starting in 2002, Rolex began etching tiny crowns onto the crystal of each watch. They’re tough to see with the naked eye—often requiring a jeweler’s loupe and a bit of patience—but if you’re looking at a Submariner made after 2002, you will see it there. If you don’t, you’re probably looking at a fake.

Dead Giveaway #5: The Price … and the Place

As the old saying goes, “If a deal seems too good to be true … it probably is.” And this is especially true when it comes to the world’s most popular luxury watches …

So if you find a Submariner selling for prices well below market, you might want to be suspicious. Likewise if you find yourself buying a watch from somewhere that seems less than reputable.

There’s another saying in the luxury watch community, that you’re buying the seller as much as you’re buying the watch. So if you don’t feel like you can trust the seller, you might not be able to trust the watch either.

If you’re at all doubtful about the provenance of your timepiece, then you might want to keep shopping around. After all, a real Rolex Submariner should last you a lifetime—so there’s no rush to grab yours right away.