The short answer
A fake IW329107 is a replica of the IWC Aquatimer, a 42 mm steel dive watch. Replicas of this reference usually fail in three places: the movement inside, the bezel mechanism, and the water resistance. To judge one, measure the case, compare the dial and caseback against IWC's published reference sheet, open the watch to identify the movement, and pressure-test the case before it goes near water.
What the reference covers
IW329107 sits in the IWC Aquatimer line, the brand's dive range. The model uses a stainless steel case, a rotating dive bezel, an automatic Swiss movement, and a water resistance rating that IWC lists per reference. Case diameter, thickness, lug width, crystal type, and strap hardware all appear on the official sheet. Treat that sheet as the baseline. Photos from a listing are not enough to judge a replica, because lighting hides case finishing and dial printing.
Before you start
- Digital calipers with 0.01 mm readout
- A 10x loupe or a macro lens
- The official reference specification from IWC
- A watchmaker who can open a caseback and run a pressure test
How to evaluate a fake IW329107
- Download or print the reference sheet for IW329107 and note the case diameter, thickness, lug width, movement calibre, and water resistance.
- Measure the case diameter across the bezel with digital calipers and write the number down.
- Measure the thickness from caseback to crystal and compare it with the spec, since replica cases often run thick.
- Check the lug width against the strap or bracelet, looking for gaps that a genuine fit would not have.
- Inspect dial printing with a loupe, comparing font weight, letter spacing, and the position of the date window.
- Rotate the bezel through a full turn and count the clicks, then check that the marker at 12 lines up with the dial.
- Unscrew the crown and feel the threading, then check that the stem sets the date and time without grinding.
- Have a watchmaker open the caseback and identify the movement, noting the calibre number and the level of finish.
- Compare the caseback engraving depth and the serial format against reference photos of the model.
- Pressure-test the case to the rated depth and ask for the result in writing.
- Weigh the head on a postal scale and compare it to the figure other owners report for the genuine watch.
Red flags in low-grade replicas
- Case size off by 0.5 mm or more
- Bezel with a mushy action or no defined click
- Movement that does not match the calibre number for the reference
- Dial text that is too bold, too thin, or spaced wrong
- Seller who will not show photos of the movement or the caseback
- Water resistance claimed with no test report
Legal and ownership notes
In the United States, importing or selling a watch that carries a protected trademark without permission is illegal, and shipments can be seized at the border. Personal ownership is a separate question from resale, but selling a replica as genuine is fraud. If you keep a replica, do not have it serviced as a genuine IWC, and do not dive with it until an independent pressure test confirms the seals hold. A failed gasket at depth damages both the movement and the case.