A fake IW371431 is a counterfeit version of the IWC Portugieser Chronograph reference IW371431, a stainless steel chronograph from the IW3714 family. Copies capture the shape from a distance, but the dial printing, subdial placement, pusher feel, and caseback engraving give them away up close. If you only have a few minutes and a phone camera, study the dial first, then the movement through the caseback.

What the IW371431 actually is

The IW371431 sits inside the Portugieser Chronograph line, whose core reference is the IW3714. Watches in this family share a simple recipe: a round stainless steel case just over 40 mm across, a clean dial with two subdials stacked on the vertical axis, applied Arabic numerals, leaf-shaped hands, and a two-pusher chronograph. In most versions the 30-minute counter sits at 12 o'clock and running seconds sit at 6 o'clock, driven by the caliber 79350, a Valjoux 7750 derivative. Because the design is symmetrical and uncluttered, it is also a favorite target for counterfeiters.

Dial details that expose a fake

The dial is where most fakes fail, because printing fine text at small scale is hard to do well.

  • Lettering quality. Brand text and model markings on genuine dials have sharp edges and even spacing. Fakes show thick, fuzzy, or crowded letters, and the text may sit off center below the 12.
  • Subdial position. Both counters should line up on the vertical axis with equal margins from the numerals and the outer minute track. A subdial that drifts to one side is a strong warning sign.
  • Hand shape. Leaf hands should be flat, tapered with an even edge, and polished along the bevel. Replicas often use thicker hands or dull finishing that catches light in patches.
  • Numerals. Applied numerals should sit flush with clean edges. On fakes they can look glued on or raised in the wrong place.
  • Date aperture, if fitted. On any reference with a date, check that the window edges are crisp and the disc centers correctly.

Case, crown, and caseback

Case work is the second filter. Genuine cases have tight lug lines, a crown that turns with light resistance, and pushers that start and reset the chronograph with a short, clean click. Counterfeits tend to have mushy pushers, a gritty crown, and lugs that look thick from the side.

Turn the watch over. The caseback engraving on a genuine watch is cut deep and reads clean, and the reference and serial numbers between the lugs are struck, not printed. Many fakes use shallow laser etching that looks gray and flat, or they carry a reference number that does not match the dial layout. Weight is a useful signal: a steel Portugieser Chronograph has a substantial feel, while many fakes use lighter alloys or a hollow case.

Movement and finishing

Open the caseback and the gap becomes clear. The caliber 79350 shows a decorated rotor, perlage or Geneva stripes on the bridges, blued screws, and clean engraving of the caliber and brand markings. Cheap copies hide a generic Asian chronograph movement behind a stamped plate. Look for shallow rotor engraving, unfinished bridges, plastic movement spacers, and a chronograph seconds hand that stutters or snaps back instead of sweeping and resetting clean.

Fake, replica, and homage: what the words mean

  • Fake or counterfeit: a watch built to be sold or worn as the genuine article, branding and all.
  • Replica: a watch that copies the design and often the branding, but is sold openly as a copy.
  • Homage: a watch that borrows design cues without copying the brand name.

The distinction matters when you read listings. A seller who avoids the word replica and calls a watch "authentic" or "from an estate" carries a different risk than one who states up front that it is a replica.

Red flags in listings and pricing

  • A price far below the going rate for the reference.
  • Blurry photos, or no photos of the caseback and movement.
  • Stock images used instead of photos of the actual watch.
  • Vague answers about service history, box, and papers.
  • Pressure to pay outside a protected payment method.

How to check a watch before you buy

  1. Request high resolution photos of the dial, caseback, movement, and clasp.
  2. Compare the reference and serial numbers with official IWC documentation for the model.
  3. Have an independent watchmaker open the case and confirm the movement.
  4. Buy from sellers with a verifiable history and a return window.

Quick recap

A fake IW371431 is judged on three things: how the dial is printed, how the case and pushers feel, and what sits behind the caseback. Get photos of all three before you commit, and treat any missing detail as a reason to walk away.