Answer

A fake IW329121 fails one or more of four checks: the caseback engraving, the movement, the dial printing, and the paperwork. Confirm the reference exists in IWC's catalog first. Then inspect the caseback with a loupe. Then ask for movement photos.

IWC writes reference numbers as IW plus six digits. The IW3291xx block covers more than one model family, so the model name a seller gives you does not always match the number. Confirm the name, case size, and caliber on IWC's own catalog page before you pay. If you cannot find the reference there, stop.

Caseback engraving

Genuine IWC casebacks carry the reference and a serial number cut into the metal. The cut is sharp and even. Replica casebacks use shallow laser etching or paint fill. Run a fingernail over the digits. Real engraving catches the nail. Paint does not. Check the words "International Watch Co." and "Schaffhausen." Replica stamps drop letters.

Movement

Ask for a photo of the movement with the caseback open, or a video of the seconds hand. IWC fits in-house calibers and modified third-party calibers. A genuine caliber runs at 4 Hz, or 28,800 vibrations per hour. Cheap replica movements run at 3 Hz and the seconds hand stutters. A rotor with etched text, no jewel count, and no finish marks is a warning sign.

Dial, hands, and crystal

  • Applied indices sit level and flush. Replica indices sit high or crooked.
  • Lume is even under UV. Replica lume is blotchy.
  • The date window edge is chamfered. Replica windows show raw stamped edges.
  • Anti-reflective coating shows a blue or purple tint at an angle. Many fakes skip it.

Price and paperwork

Used steel IWC watches in this reference block sell between about $3,000 and $6,000 depending on model, year, and box and papers. A new-looking example at $400 is counterfeit. Ask for the warranty card, the booklet, and the original invoice. Check that the serial on the card matches the caseback.

Before you buy

  1. Find the reference on IWC's site.
  2. Match case size, caliber, and dial layout.
  3. Get movement photos.
  4. Have a watchmaker open the case.
  5. Pay after inspection, not before.