Short answer
A counterfeit IW329081 fails at four points: the caseback engraving, the dial printing, the movement finish, and the paperwork. A 10x loupe and a set of calipers settle most questions in under five minutes. If one check looks wrong, treat the watch as fake and walk away.
Before you start
- A 10x jeweler's loupe
- Digital calipers reading to 0.1 mm
- A scale reading to 1 g
- Bright angled light and a clean white surface
- A phone camera for macro shots of the caseback and movement
Work on a soft cloth. Do not open the caseback unless you own the watch or the seller agrees in writing.
Checks in order
- Confirm the reference exists. Look up IW329081 in the maker's own catalog data and match the case size, dial layout, and movement name. If no catalog entry matches, stop there.
- Set the watch flat and photograph the caseback in raking light. Genuine engraving has crisp walls and even depth. Fake engraving looks soft, rounded, or shallow in the middle of each letter.
- Compare the caseback text to the catalog: reference, case material, water resistance, and country of origin. Font weight and letter spacing matter as much as the words.
- Examine the dial print with the loupe. Genuine print sits flat with sharp edges. Counterfeit print shows thick edges, uneven spacing, or ink bleed on the small text.
- Check the date window. Look at the window edge, the date font, and the alignment at 12, 15, and 28. A crooked or off-center date wheel is a common fake fault.
- Inspect the crown and any pushers. Genuine threads engage in one smooth turn, the logo relief is sharp, and the crown seats flush against the case. Fakes feel gritty or sit proud of the case.
- Measure the case with calipers and weigh the head on the scale. Compare both numbers to the catalog specification. A 0.5 mm difference or a 20 g gap points to a fake case.
- Ask to see the movement through a display back. Check rotor finishing, perlage or Geneva stripes, screw heads, and the jewel count. Look for the maker's engraving on the bridge.
- Look at the crystal at an angle. Genuine sapphire shows a faint anti-reflective tint on both faces. Most fakes coat one side or show a heavy purple or blue cast.
- Compare the serial on the caseback with the serial on the warranty card and the movement. The fonts must match each other, and the card must carry the correct reference.
- Check the price against the secondary market for the same reference. A price far below the going rate is the strongest single signal of a fake.
- Take the watch to an independent watchmaker and have the case opened. A movement photo and a timing reading on a timegrapher end the argument.
Where fakes score points
- Case shape and overall proportions, which modern CNC machining copies with ease
- Strap stitching and buckle shape on common references
- Box, manual, and card printing, which copies well at low cost
- Weight on solid steel cases, which lands close to the real number
Do not let a good case shape carry the decision. Grade the four checks that matter: engraving, dial print, movement finish, and serial match.
When to stop
- The seller refuses to let a watchmaker open the case
- The reference does not appear in the maker's catalog
- Serials do not match across caseback, movement, and card
- The price sits far under the market