Quick answer

IW329037 is an IWC reference number. IWC uses the pattern IW plus six digits. The 3290 block covers Aquatimer Automatic models: 42 mm steel dive watches. I could not confirm IW329037 in public IWC catalogs at the time of writing. Ask the seller for the IWC catalog page or a caseback photo before you pay. A replica built on a number IWC never made is a warning sign.

What the genuine 3290 block tells you

Aquatimer Automatic watches in this block share these traits: 42 mm case, about 14 mm thickness, sapphire crystal, screw-down crown, date at 3 o'clock, and 300 m water resistance. The IWC caliber 32111 runs at 28,800 vph and holds a 120-hour power reserve. IWC states the 32111 is based on Sellita SW300 architecture. That 120-hour figure is the easiest number to test.

How replicas of this block are built

  • Case steel: 316L is common. Genuine Aquatimer cases use 316L on most references. Some high-tier replicas claim 904L.
  • Movement: Miyota 9015, Seiko NH35, or a Chinese clone of the ETA 2892 or Sellita SW300. A Miyota 9015 runs at 28,800 vph with a 42-hour reserve.
  • Case size: measure it. Replicas of a 42 mm case often come in at 42.5 to 43.5 mm.
  • Water resistance: most replicas leave the factory without a pressure test. Gaskets and caseback threads are the failure points.

Checks before you pay

  1. Ask for the reference engraved between the lugs. It should read 329037.
  2. Ask for a timed power reserve test. Genuine spec is 120 hours. A Miyota or NH35 build stops at 40 to 45 hours.
  3. Ask for case measurements taken with calipers, not a ruler.
  4. Ask for a pressure test result at 3 bar minimum if you plan to swim in it.
  5. Ask for 10x macro photos of the dial print. Poor print on a diver is the first tell.

Price bands

Replica Aquatimer-style watches sell in three bands. Entry: $70 to $150, quartz or a low-grade automatic. Mid: $180 to $400, Miyota or NH35 inside. High tier: $450 to $800, clone movement with decorative plates and closer case finishing. No replica at any price uses the IWC 32111. IWC does not sell that caliber to third parties.

Legal note, US

Counterfeit watches are illegal to import into the United States. Customs and Border Protection can seize the shipment. 19 CFR 133.23 covers the rules. A replica is not a genuine IWC and carries no IWC warranty or service support.