The 26574 replica is a real product on the market, sold as an "AP 26574 super clone" or a "1:1 Royal Oak perpetual calendar." It photographs well. Pick it up and the story changes. The genuine Royal Oak Perpetual Calendar ref. 26574 measures 41mm across and roughly 9.5mm thick, carries a week-of-year scale around the dial rim, and runs Audemars Piguet caliber 5134, an ultra-thin automatic with a true perpetual calendar stacked on top. No copy of this reference gets the whole package right. Most measure 11.5mm to 12.5mm, and the calendar is decoration rather than a mechanism.
What the 26574 actually is
- Royal Oak case, 41mm, about 9.5mm thick, octagonal bezel held by eight hexagonal screws.
- Caliber 5134, built on the long-lived 2120 automatic (2.45mm thick) with a perpetual calendar module added.
- Full perpetual calendar: day, date, month, leap year, moon phase, and week of the year, with no correction needed before 2100.
- Materials run steel (26574ST), then yellow gold, titanium, and platinum. Steel examples on the secondary market sit deep into five figures in US dollars.
Thickness is the first tell
Calipers end the conversation fastest. A real 26574 sits just under 10mm on the wrist, with recessed correctors set flush into a thin caseback. A copy built on a modified chronograph base or a generic Chinese automatic has to hide a thicker movement stack, so the case grows and the profile looks puffy. Anyone who has worn a Royal Oak notices right away, because a thick case pushes the bracelet away from the wrist instead of draping against it.
The calendar usually lies
A perpetual calendar is not a triple date. On a genuine 26574 the subdials and the rim scale advance together, the leap year indicator follows a four-year cycle, and the moon phase tracks the 29.53-day lunar month. On replicas, the common outcomes:
- Month and date move independently, or the leap year hand never moves at all.
- The moon phase disc turns once every 24 hours instead of once every 29.5 days.
- The week-of-year scale is printed and dead, with no hand to drive it.
- The caseback correctors do nothing, or jam after a few pushes.
The fastest test: set the watch to a 30-day month and advance the date past the end of it. A perpetual calendar rolls from the 30th to the 1st and skips the 31st on its own. Most copies land on the 31st and then need manual correction.
Dial and bracelet
The 26574 uses the Grande Tapisserie dial, stamped and then finished to a sharpness that cast or press-copied dials lose. Subdial hands are thin, flat, and polished with a bevel you can see under a loupe. Replica hands are often too thick or subtly curved. The bracelet is harder to fake than the watch itself: the taper from case to clasp, the bevel on every link, and the fit of each screw head all show up on the wrist. Screw slots that sit proud of the bezel or run off center are a giveaway, and the same goes for brushing that changes direction without reason.
Movement
Turn a 26574 over and you see the 5134: gold rotor, Geneva stripes, circular graining on the mainplate, bevelled bridges, and engraved text with depth. A replica typically shows a decorated plate with an engraved rotor that mimics AP lettering but gets the fonts wrong. The finishing is machine-applied, so it looks flat under angled light, and the calendar module on top is often a thin plate with fake screws.
Checks that settle it in a minute
- Measure thickness. Over 10mm and the case is wrong.
- Read the week-of-year scale. No hand, stop there.
- Advance the date across the end of a 30-day month.
- Push each caseback corrector and watch which subdial responds.
- Inspect screws, hands, and the dial pattern under magnification.
- Ask who services it. Audemars Piguet will not touch a counterfeit, and independent watchmakers who know the 5134 will not either.
The legal and money problem
In the United States, trafficking in counterfeit goods is a federal offense under 18 U.S.C. § 2320, and CBP seizes counterfeit watches at the border as a matter of routine. A shipped replica can be destroyed with no refund, and the buyer has no recourse. Resale is worse: no auction house, no established dealer, and no serious forum will list it, so the money is simply gone. Add an unserviceable movement, and a copy that stops stays stopped. That is a lot of downside for a watch that gets the calendar functions wrong on the first inspection.
Bottom line
If the goal is a perpetual calendar on the wrist, the 26574 is one of the hardest references in the market to copy, and the copies show it from every angle: thickness, functions, finishing, and legal exposure. Buy the real watch from a dealer with papers, or choose a complication you can actually own. Either route beats a thick case with a moon phase that laps the dial once a day.