Short answer

IWC publishes its chronographs under reference families such as IW3714 (Portugieser) and IW3717 (Pilot's Watch Chronograph). We could not confirm a public IWC catalog entry for IW371780. Sellers use the number for a 42 mm steel chronograph with a black dial, a day-date window at 3 o'clock, and three subdials. Treat IW371780 as a seller label until a catalog page confirms it.

What the number implies

The IW3717 family covers the Pilot's Watch Chronograph Automatic, produced from 2006 onward. Specs for that family: 42 mm steel case, about 14.6 mm thick, sapphire crystal, 60 m water resistance, and the IWC cal. 79320 movement. Cal. 79320 is a Valjoux 7750 base, 25 jewels, 28,800 A/h, about 44 hours of reserve. Replica versions copy that layout, not the internals.

Price tiers and what you get

  • $60 to $120: quartz movement, mineral glass, printed dial, chrome-plated hands, stamped caseback.
  • $150 to $300: Asian automatic 7750 copy, 28,800 A/h, sapphire front, steel case, glued-on numerals.
  • $350 to $600: modified 7750 with a decorated rotor, sapphire on both sides with antireflective coating, engraved caseback, correct date font.

Checks before you pay

  1. Ask for the movement name and beat rate. A 21,600 A/h answer means a lower grade.
  2. Request a photo of the subdial hands at the 12 o'clock counter. A 7750 copy sweeps and resets to zero.
  3. Confirm case thickness. Thin cases under 13 mm hide a quartz module.
  4. Check the day-date font. Wide, bold digits are a common tell.
  5. Ask about the crown position. On a 7750 the crown sits at 3 o'clock with pushers at 2 and 4.

Legal position in the US

Trafficking in counterfeit goods falls under 18 U.S.C. 2320. First-offense penalties reach 10 years and $2 million. US Customs can seize shipments and holds the right to destroy them. Resale of a counterfeit watch as genuine adds fraud exposure.

What we could not verify

Production years, dial variants, and case metal for IW371780. No IWC service document or catalog page for that number appears in public search results. If a seller cites a limited edition, ask for the IWC certificate number and check it against the brand's database.