A fake IW371647 gives itself away in three places: printed dial text, case finishing, and paperwork. The IW371647 sits in IWC's 3716 reference family, the Portofino Chronograph 39, so any counterfeit has to copy a 39 mm steel case, a chronograph layout, and IWC's own dial typography at the same time. Under a loupe, most fakes fail on the first two, and an IWC service center will confirm it on the third.
What exactly is the IW371647?
The IW371647 is a Portofino Chronograph 39, a stainless steel chronograph in IWC's entry-level dress-sport line. IWC reference numbers work as a family plus variant system: the first four digits (3716) identify the model, and the trailing digits identify the dial, strap, and finish combination. Because the variants look similar, counterfeiters often stamp one reference number across several different dial colors, which is itself a red flag.
How can you tell a fake IW371647 from a genuine one?
Start with the dial, because that is where replica factories cut costs most often. Genuine IWC printing is razor sharp with even letter spacing, while counterfeit text tends to look slightly thick, uneven, or glossy. Then check the case and the paperwork, since a real Portofino is sold with a warranty card, a numbered caseback, and a documented service history.
Dial and printing checks
- The IWC wordmark and "SCHAFFHAUSEN" should be crisp and evenly spaced, with no blur or double edges under magnification.
- Applied indices should sit flat and flush, with no glue squeeze-out or uneven polishing at the edges.
- The date font should be thin and correctly centered in the window, not bold, off-center, or clipped at the top.
- Subdial hands should reach the printed track exactly, since short or long hands are a common replica tell.
- Hands and indices should carry an even lume fill, with no bubbling or color mismatch between them.
Case, crown, and pusher checks
Genuine Portofino cases show a clean line between brushed and polished surfaces, with sharp lug edges and no soft rounding. Fake cases often feel lighter than expected and can show tool marks inside the lugs, where finishing is usually skipped. Push the chronograph pushers: a real movement starts and resets with a firm, clean click, while cheap replicas feel spongy or reset unevenly.
Caseback and movement checks
The Portofino Chronograph 39 uses a solid caseback, so the movement is not visible on the wrist and a seller cannot show you one. Engraving on the back should be deep, crisp, and correctly aligned, with a reference and case number that match the paperwork. If a watchmaker opens the case, movement finishing, rotor engraving, and the balance assembly separate a genuine IWC calibre from a generic clone in seconds.
What do box, papers, and price tell you?
Genuine Portofino Chronograph models sell in the four-figure USD range on the secondary market, so a sealed box at a few hundred dollars is not a bargain. A warranty card with a mismatched serial number, or a listing that uses stock photos instead of its own images, points to a counterfeit or a misrepresented watch. Ask for a photo of the caseback numbers and the warranty card in the same frame before you send money.
Are high-end replicas of the IW371647 convincing?
Modern top-tier replicas can pass a glance across a table, and some copy dial printing closely enough to fool an untrained eye. What they rarely copy is movement architecture, so a watchmaker's inspection remains the only reliable test. Treat any IW371647 sold as a "1:1" or "super clone" as a replica by definition, not a genuine watch, and price it accordingly.
Quick pre-purchase checklist
- Compare dial printing and subdial hand lengths against verified photos of the reference.
- Weigh and measure the watch: the Portofino Chronograph 39 is 39 mm across and should not feel hollow.
- Confirm the caseback reference and serial match the warranty card and any service papers.
- Have a qualified watchmaker inspect the movement before final payment.
- Walk away if the price sits far below the market range for the reference.