Short answer

A replica IW371481 copies the IWC Portugieser Chronograph. The original is a 40.9 mm stainless steel watch with two subdials: a 30 minute chronograph counter at 12 and small seconds at 6. Replicas come in three tiers. Quartz, entry automatic, and Valjoux 7750 based automatic. Prices run from about USD 50 to USD 400. Build quality tracks the tier, not the reference number engraved on the caseback.

What the reference number covers

IW371481 sits in the IWC Portugieser Chronograph family. IWC uses one base case and changes dial, hands, strap, and metal per reference. The reference number is a dial and strap combination, not a separate watch design. Confirm the exact dial color and strap for this number against IWC's own listing. The number alone does not fix the finishes.

Original specifications

  • Case diameter: 40.9 mm
  • Case thickness: 12.3 mm on steel models
  • Crystal: sapphire with antireflective coating on both sides
  • Water resistance: 3 bar, about 30 m
  • Movement: IWC calibre 79350, based on the Valjoux 7750, 44 hour power reserve, 28,800 vibrations per hour. Newer Portugieser Chronograph models use calibre 69355.
  • Dial: two registers. Chronograph minutes at 12. Small seconds at 6. No date on most references.
  • Strap: alligator leather on most references

How replicas differ

  • Thickness. Many replicas measure 13 mm to 14 mm, about 1 mm more than the original, because the clone movement is thicker.
  • Movement. Quartz versions use a battery module. Automatic versions use a 7750 clone. Some sellers decorate the rotor with IWC markings.
  • Numerals. The original uses applied numerals. Low tier replicas print them. Mid tier replicas apply them with softer edges.
  • Crystal. Mineral glass on low tiers. Sapphire on higher tiers.
  • Chronograph action. A 7750 clone sweeps at 8 beats per second and the pushers feel firm. A quartz chrono steps once per second.

Checks before you pay

  1. Ask the seller to name the movement. If no name comes back, treat the listing as unknown.
  2. Ask for a caliper photo of case diameter and thickness.
  3. Confirm the subdial layout is at 12 and 6.
  4. Confirm there is no date window if the reference has none. Many replicas add one.
  5. Ask for the weight. A steel head at this size runs about 70 g to 90 g without the strap.
  6. Study the caseback photos. The depth and font of the engraving show the tooling used.

Price tiers

Quartz replicas sell for about USD 50 to USD 120. Automatic 7750 based replicas sell for about USD 180 to USD 400. Sellers asking above USD 400 for this reference claim Swiss parts. Ask for movement photos before paying that.

Legal note for US buyers

US Customs and Border Protection can seize counterfeit goods at import. Importing a replica that carries a protected trademark is prohibited under 19 U.S.C. 1526. A seized parcel is not returned, and carriers do not refund the shipping fee.