Answer First

IW329171 is an IWC reference number in the Aquatimer Automatic 42 family. A replica that carries this number copies a 42 mm steel dive watch with a rotating dive scale and a 300 m water resistance rating on the genuine version. Replica builds use third-party movements, not the IWC calibre 32111. No replica comes with IWC service or warranty.

What the Digits Mean

IWC writes references as IW plus six digits. The first four digits name the family. The last two digits name one version inside that family.

  • IW3291: Aquatimer Automatic 42, steel case, 42 mm.
  • Final two digits: dial color, strap type, or case finish for that version.

The public IWC spec sheet for the exact 71 variant is not something this page can confirm. Treat any listing claim about dial color or strap as unverified until you see photos of the item.

Genuine Specs to Compare Against

  • Case: stainless steel, 42 mm diameter, about 14 mm thick.
  • Crystal: sapphire with anti-reflective coating.
  • Movement: IWC calibre 32111, based on the Sellita SW300-1, 120-hour power reserve.
  • Water resistance: rated to 300 m.
  • Strap: rubber or steel, set by the version.

What Replica Listings Promise

Common claims: 1:1 case size, sapphire crystal, screw-down crown and caseback, an automatic movement, and the same 300 m rating. Claims differ from seller to seller. Check each one.

Checks Before You Pay

  1. Ask for caliper photos of case width, lug to lug, and thickness.
  2. Ask for the movement name. Common options are a cloned 32111 layout, a Miyota 9015, or a Sellita SW300.
  3. Ask for a clear photo of the caseback text and the crown threads.
  4. Get the return window in writing.
  5. Book a pressure test at a watchmaker after delivery. Cost in the US runs about $30 to $60.

Limits

A replica leaves the factory with no gasket test. ISO 22810 sets the standard for dive watch ratings and marking. A third-party build does not carry that certification. Do not dive with a replica. Parts and service come from the seller, not from IWC. Resale value is near zero. US law treats counterfeit goods as illegal to import and sell, so a replica stays a private purchase with no legal recourse.