Short answer

IW323729 is the IW3237 IWC Ingenieur Automatic with a two-digit variant suffix. IWC prints the model code as IW3237 and marks dial and strap versions with a number such as 29. Sellers who drop the hyphen write it as IW323729. A fake IW323729 is a copy of that steel watch, not a different model. Copies sell for about $150 to $400. Used real ones list between $3,000 and $6,000.

What the reference covers

The IW3237 block sits in the Ingenieur Automatic line. Case size is 40 mm. The case is steel with an integrated bracelet. Water resistance is 10 bar. The movement is IWC calibre 30110, built on the ETA 2892-A2, running at 28,800 vibrations per hour with about 42 hours of power reserve. The Ingenieur name dates to 1976 and the ref. 1832 SL designed by Gerald Genta. A flat bezel with screws and the integrated bracelet carry through the line.

Signs of a copy

  • Crystal. Real watches use sapphire with anti-reflective coating on both faces. Copies use mineral glass. Reflections are stronger and the edge looks green or grey.
  • Case back. Real engraving is deep and even. The reference, case number, and "Swiss Made" sit in a straight line. Copy engraving is shallow and the font is wrong.
  • Dial printing. Check the IWC logo, the word Automatic, and the minute track. Copies show thick letters and uneven spacing.
  • Bracelet. Real end links are solid and meet the case with no gap. Copies rattle and use stamped clasps.
  • Movement. Calibre 30110 is mechanical, so the seconds hand sweeps. A ticking hand means a quartz copy. IWC did not fit quartz to this reference.
  • Weight. A steel 40 mm watch on a full bracelet feels heavy. Copies use lighter alloys and thin cases.

Paperwork checks

Ask for photos of the movement, the case back, and the warranty card. Genuine IWC paperwork carries the reference and the case number. Those two numbers must match the watch. Both can be checked at an IWC boutique or an authorized service center. A seller who refuses a movement photo is a risk.

US import rules

19 U.S.C. 1526 lets U.S. Customs seize and destroy counterfeit shipments. Trafficking in counterfeit goods is a federal crime under 18 U.S.C. 2320. The IWC name and the case design are covered by registered trademarks.

Unknown points

IWC does not publish a full list of dial codes. Public sources do not document which dial the 29 suffix marks. Confirm the variant with IWC before you buy or sell.