The Short Answer

The IW371752 sits in IWC's Portugieser Chronograph family: a steel chronograph with a twin-register dial and a very clean face. When someone searches for a "fake IW371752," they mean one of two things. Either they want a replica of that reference, or they are looking at a watch sold as the real thing and want to know if it is a copy. The second case is the expensive one, because the money on the table is real. If you are buying a replica, your job is to pick a version that gets the proportions and the dial print right. If you are buying what claims to be genuine, your job is to verify the movement, the caseback stamping, and the paperwork before anything changes hands.

What the Reference Looks Like

The Portugieser Chronograph is a 41 mm steel case with a thin bezel, a domed sapphire crystal, and a dial built around two subdials: running seconds at 6 o'clock and the 30-minute chronograph counter at 12. The date sits at 3. Hands are leaf shaped, the numerals are applied, and the whole thing reads as a dress watch that happens to time things. Dial colors vary by version, from silver-plated to blue to black, and the finish ranges from matte lacquer to sunburst. Sapphire casebacks are common on this line, which matters, because it means you can see the movement without opening anything.

The Tells I Check First

  1. Dial print. "IWC" and "Schaffhausen" should be thin, evenly spaced, and sharp at the edges under a loupe. Fakes run a heavier font or drop the text a fraction too low.
  2. Date wheel. The numeral font and the way it sits in the window. Real discs sit flush and use a specific typeface. Cheap replicas show a squarer numeral and a window that looks machined instead of polished.
  3. Subdial alignment. The two subdial centers should share one vertical axis, and the hands should match in length. Replicas often miss by a hair, and it shows in photos.
  4. Case profile. The lugs curve down and inward. Generic replica cases are thicker and the lugs sit flatter against the wrist.
  5. Crown and pushers. IWC pushers are smooth and sit close to the case. Entry-level replicas use oversized pushers with knurling you can feel.
  6. Antireflective coating. IWC's coating has a faint blue cast. A purple or yellow flash under light is a warning sign.

The Movement Is Where Most Fakes Fall Apart

Push the chronograph button. The start should feel light and precise, the hand should jump once, and the reset should snap back to zero with no stutter. Replicas built on a modified 7750 base or a Chinese chronograph module feel stiff, and the seconds hand often lags on reset. Ask for a movement photo. On the genuine article the rotor engraving is cut into the metal, not stamped on top, and the finishing under it stays consistent across the bridges. On replicas you see striped finishing that stops at the edge of a bridge, or engraving that looks printed.

Papers, Serial, and Caseback

Reference and serial numbers are stamped between the lugs, and they should match the paperwork. A missing warranty card is not proof of a fake, but a card with a mismatched reference number is. Ask the seller for the serial and compare it to the listing before you commit. On a replica, the stamping is often shallow and the spacing between characters is uneven.

If You Are Buying a Replica on Purpose

Replicas come in tiers, and the gap between them is mostly in the small stuff: dial print quality, AR coating, the movement decoration, and the strap and buckle. A mid or high tier copy of the Portugieser Chronograph gets the dial layout and the case thickness close. The cheapest tier gets the thickness wrong, and that is the first thing anyone notices in person. Buy from a seller who posts macro photos of the dial, the crown side, and the caseback. If a listing only shows renders or stock images, that tells you enough.

Accept the trade-offs too. A replica chronograph will not hold value, a service can cost more than the watch, and water resistance is a claim rather than a fact. Do not swim with it.

Questions to Ask Before You Pay

  • Can you send macro photos of the dial print and the date window?
  • Which movement is inside, and does the chronograph hand reset to zero cleanly?
  • What is the measured case diameter and thickness?
  • Is the strap signed, and is the buckle the correct shape?
  • What happens if the watch does not match the photos?

Five minutes of questions saves a lot of regret. On this reference, the dial and the movement tell the story, and both are easy to photograph if the seller is being straight with you.