A fake IW371471 is a counterfeit of the IWC Portugieser Chronograph from the 3714 family, and the better ones are convincing enough that photos alone rarely settle the question. The reference is a steel chronograph with a clean dial and a movement that is easy to recognize once you know the layout. What separates a replica from the real thing shows up in three places: how thick the case sits, how the movement behaves when you start and reset the chronograph, and how fine the dial printing looks under magnification.

What the genuine watch looks like on paper

The published specs for the 3714 family put the case at about 40.9 mm across and roughly 12.3 mm thick, in stainless steel with a sapphire crystal coated on both faces. Water resistance is low, rated around 3 bar, which is normal for a dress chronograph. Inside sits caliber 79350, a reworked Valjoux 7750 running at 28,800 vibrations per hour with about 44 hours of reserve. The dial is bicompax: running seconds at 6 o'clock, 30-minute chronograph counter at 12. Nothing about that layout is exotic, which is exactly why it gets copied.

Why this reference gets cloned so hard

A plain steel chronograph is the easiest luxury watch in the world to fake. No moonphase, no annual calendar, no precious metal case to match. A replica maker buys an Asian 7750 or a clone, machines a case, prints a dial, and gets most of the way there on paper. The last stretch is what costs money, and it is the stretch you notice on the wrist within a day.

Case and crystal checks

  • Measure the thickness with a caliper. Genuine 3714 references sit near 12.3 mm. Replicas built on an Asian 7750 usually land between 13.5 and 14.5 mm, and you can feel the difference the moment the watch sits under a cuff.
  • Study the crystal at an angle. Double-sided anti-reflective coating gives a faint blue-violet sheen and kills most reflections. One-sided or uncoated crystals look flat and gray, and the dial behind them loses depth.
  • Run a fingertip along the lugs. Real IWC lugs are thin, tapered, and polished to a mirror with crisp transitions. Reps feel a touch soft or rounded where the lug meets the case.
  • Check the crown. It should turn smoothly, seat flush, and carry clean engraving on the end. Replica crowns often have shallow or off-center lettering.

Dial printing and hands

  • Compare dial text against a dealer photo at high magnification. Genuine printing has sharp edges and even spacing. Replicas show thick strokes, fuzzy serifs, or text that sits a hair too low under the logo.
  • Watch the running seconds hand. At 28,800 vph it sweeps in eight small steps per second. A replica with a 21,600 vph movement ticks in six, and the difference is obvious side by side.
  • Check that the two subdials sit on a true vertical line through the center of the dial. Reps sometimes crowd the upper subdial toward 12 or drop the lower one.
  • Look at hand finishing. Genuine hands are polished on the bevels with clean edges. Replica hands look grainy or slightly thick.

Movement and caseback

If the reference you are comparing has a display back, the movement is the giveaway. The 79350 is a 7750 base, so you will see a rotor, a balance, and a chronograph bridge. Genuine examples show a signed rotor and reasonable finishing on the bridges. Replicas show a rough rotor, missing or wrong engraving, and a bridge shaped unlike the real part.

Even behind a solid back, the chronograph tells you things. Start it and watch the minute counter. The pusher should have a firm, short travel and a clean click. Reset should snap the hands back to zero in one motion. Replicas often feel mushy, and the reset hand drifts slightly past zero.

Box, papers, and price

Replica sellers ship boxes, booklets, and warranty cards because buyers expect the full set. Check that the serial on the card matches the caseback engraving, and look at the print quality on both. Paperwork is cheap to fake, so treat it as supporting evidence, not proof. Price is the fastest test of all. If the asking price is a small fraction of what the same reference brings on the secondary market, the listing has already answered the question.

The legal side

In the United States, trafficking in counterfeit goods is a federal offense under 18 U.S.C. § 2320. U.S. Customs and Border Protection seizes counterfeit watches at the border, and an import can mean losing both the watch and the money. That risk is worth pricing in before you send payment to anyone.

Bottom line

Thickness, crystal coating, dial print, and movement beat rate will catch nearly every fake IW371471. Measure the case, look at the crystal at an angle, count the seconds-hand steps, and compare the price to reality. If two or three of those checks come back wrong, walk away.