The short answer
IW371779 is a reference number you run into on replica listings, not on IWC's own pages. It looks like a Portugieser Chronograph number because it borrows the shape of one, six digits after the IW prefix, but it does not line up with a documented IWC reference the way IW3714 or IW3716 do. When a seller uses it, they are usually describing a fake Portugieser Chronograph and dressing it up with a number that sounds official.
Why the number looks plausible
IWC's reference system is compact. Two letters, six digits, no hyphens. The Portugieser Chronograph family sits in the IW3714xx and IW3716xx range, so a listing that reads IW371779 lands close enough to feel real if you are skimming. That is the point. Replica sellers mix a familiar digit string with small changes to create a model that is hard to check.
If you want to verify a reference, the brand's own product pages are the only source that settles it. Forum threads and seller pages repeat each other, and once a wrong number circulates it tends to stick.
What "1:1" and "super clone" mean in practice
These terms get thrown around in the replica market and they carry no standard definition. In practice, a high-end replica of a Portugieser Chronograph is a stainless steel case with a Chinese-made automatic chronograph movement inside, a printed or applied dial, and a sapphire or mineral crystal. Some are well finished on the outside. Almost none match the original inside.
Things that give them away:
- Subdial spacing. The Portugieser Chronograph puts running seconds at 6 and chronograph minutes at 12. Replicas often sit off center or use a different layout.
- Movement. Genuine chronographs run an in-house or heavily modified caliber. Replicas run off-the-shelf movements with no service network behind them.
- Case finishing. Brushed and polished transitions look muddy under a loupe, and edges feel sharp.
- Gold models. Plating wears through at the lugs and caseback within a year or two of regular wear.
- Water resistance. A claimed 30 or 60 meters is a guess, not a tested rating.
Legal and practical risk
Counterfeit watches are trademark-infringing goods. In the US, that matters most at the border. Customs can seize counterfeit shipments, and if you sell them the exposure moves from a seized package to civil liability, and in some cases criminal charges. Buying one for yourself carries less risk than reselling, but it is not zero.
There is also a resale problem. A replica has no market value. You cannot trade it in, you cannot insure it, and no watchmaker with a reputation will touch it. If the movement fails, you are looking at a replacement rather than a repair, and the replacement will not be the same movement.
If you are buying a used Portugieser, how to check it
- Ask for the reference on the caseback and compare it against the brand's own listing.
- Get a clear photo of the movement through the display back. Real finishing, blued screws, and perlaged bridges are hard to fake at this price.
- Look at the dial print under magnification. Sharp edges, even spacing, no bleeding.
- Feel the pushers. A genuine chronograph starts and resets with a firm, clean click.
- Check that the box, papers, and serials line up with each other and with the watch.
- Treat a price far below the pre-owned market as the loudest signal in the room.
Getting the look without the downside
If what you want is the Portugieser look on a smaller budget, the honest paths are a pre-owned genuine piece, a vintage dress chronograph from another brand, or a licensed homage with its own name on the dial. Homages copy a style, not a logo, and they come with a warranty and a service path. That is a different product from a counterfeit, and it is the one you can sell later.
Bottom line
IW371779 is not a reference you should trust. Treat it as a seller's label for a replica Portugieser Chronograph, check any claimed number against the brand's own site, and go in knowing what you give up: warranty, service, resale, and legal cover.