Short answer: treat "6204" as a seller label, not a reference you can check against Patek's own catalogue. Listings carrying that number show different watches from one seller to the next, so the digits tell you nothing about what lands in the box. Judge the watch in the photos instead: case shape, dial printing, date window, bracelet taper, and most of all the movement inside.
Why the number itself is the first warning sign
Patek is one of the most thoroughly documented makers in watchmaking, and its reference list is public. When a number cannot be matched to a known model with known dimensions, the listing is already describing a watch that does not exist in that exact form. Some sellers use it as a catch-all for a Nautilus-style steel piece, others slap it on something closer to an Aquanaut. That means the reference tells you nothing about the product, and any seller who leans on it as proof of accuracy is bluffing.
Start with measurements. Lug-to-lug, case diameter, and thickness decide whether a copy sits right on the wrist. A case that runs 1.5 mm too thick looks wrong in a mirror long before anyone reads the dial.
The three tiers, and only one is worth the money
- Budget ($80 to $200): stamped case, mineral glass, flat printed dial, chunky date font, quartz or a low-grade automatic.
- Mid ($250 to $600): 316L case, sapphire crystal, decent dial texture, Seiko or Miyota automatic, clasp that rattles when you flex your wrist.
- Upper ($700 and up): clone or modified Swiss-based automatic, correct thickness, clean brushed-to-polished transitions, solid end links, crisp date wheel, weight in the right neighborhood.
Price is not a guarantee. Mid-tier watches beat overpriced top-tier listings all the time, mostly because a seller photographed one watch and shipped another.
Details that expose a copy in the hand
Look at dial printing under a loupe, the inner edges of the date aperture, crown thread quality, caseback engraving depth, and where the bracelet changes from brushed to polished. The center links should catch light differently than the flanks. Index alignment at 12 is the usual weak spot, and the date should sit dead center at 28, 30, and 1.
Movement: the part nobody photographs
Ask for a movement shot and a timegrapher reading. A rate inside roughly ten seconds a day with healthy amplitude is a reasonable target for this category. A rotor engraved with brand markings means nothing on its own. What counts is the base caliber, beat rate, and power reserve. Skipping this step is how people end up with a watch that stops in eight months.
QC photos worth demanding
- Dial shot straight on, no tilt, so you can read index alignment
- Date centered at 28, 30, and 1
- Caseback and clasp macro shots
- Timegrapher display with rate, amplitude, and beat error
What to expect, what to avoid
Treat water resistance as decorative. Never swim with a copy, no matter what the listing claims. Service options are limited, resale is close to zero, and customs handling varies by country. If a seller promises 100 m water resistance or calls it "1:1 Swiss made," close the tab. Those two phrases show up in listings run by people who never handled the watch.
Bottom line: the 6204 name is marketing filler. Buy the photos, the measurements, and the movement, and ask for fresh QC before shipping.