Quick answer
There is no Audemars Piguet reference 15311 in the brand's official Royal Oak catalog. The number surfaces in the replica trade as a batch label, and it gets attached to copies of several different watches. Most people searching it mean one of three originals: the 39 mm ref. 15300ST, the 41 mm ref. 15400ST or 15500ST, or the 39 mm extra-thin ref. 15202ST. Identify the real reference first. Case size, dial pattern, date position, and bracelet taper all follow from that choice, and a copy that mixes specs from two references is easy to spot.
Match the real watch before you compare copies
The 15300ST uses a 39 mm case with a Grande Tapisserie dial and a date at 3 o'clock. The 15400ST and its successor, the 15500ST, step up to 41 mm with a wider dial layout. The 15202ST keeps the 39 mm case but drops to roughly 8.1 mm thick with a slimmer movement and no seconds hand on most versions. A seller who calls a watch 15311 without telling you which of these it copies is telling you nothing useful.
How the replica tiers work
Three rough grades dominate the market. Entry copies run quartz or basic automatic movements, use printed dials, and often sit 2 mm or more thicker than the original. Mid-tier copies add a cloned rotor, sapphire crystal, and a bracelet with real screws. The top grade, sold as 1:1 or super clone, uses a decorated clone movement and case dimensions that come close to the original, though close is doing real work in that sentence. Price tracks the tier, and no tier contains genuine AP parts.
Inspection checklist
- Measure the case across the bezel at 10 and 2 with calipers and compare the figure to the real reference you want.
- Count the eight bezel screws and verify that each slot lines up with the case edge, since sloppy alignment is the fastest tell.
- Inspect the dial texture under a loupe, because printed squares sit flat while a genuine tapisserie pattern is cut into the surface.
- Check the date window position and the font of the numerals against photos of the original reference.
- Flex the bracelet and study the taper from case to clasp, since copies usually keep too much width near the clasp.
- Wind the crown and listen, because a rough or grinding feel points to an unfinished movement.
- Weigh the watch and compare it to the published weight of the real piece in the same metal.
Movement reality check
No replica contains an Audemars Piguet calibre. Sellers use Miyota, Seiko, ETA clones, or Chinese automatic movements, sometimes with a decorative plate stamped to look like calibre 3120 or 2121. A decorated plate does not change the movement underneath. Ask for the base movement name in writing. If the seller will not name it, treat the watch as the cheapest grade in the listing.
Red flags
Be wary of any listing that promises same as genuine without photos of the actual unit, refuses close-ups of the caseback, or quotes a price far below the rest of the market for that tier. Water resistance claims are usually unsupported, so do not swim in a copy. Avoid sellers who offer to ship with a fake box and papers for passing off, because that turns a purchase into a fraud problem.
Legal and ownership notes
In the United States, trafficking in counterfeit goods is a federal offense under 18 U.S.C. § 2320, and Customs and Border Protection seizes counterfeit watches at ports of entry. Audemars Piguet will not service or authenticate a counterfeit, and no authorized dealer will touch it. Resale is difficult, and value drops to parts. Treat the purchase as a disposable novelty, not an asset.