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IW371615 is an IWC reference number for a Portugieser Chronograph. The watch has a 41.0 mm stainless steel case, a blue dial, a black alligator strap, and the in-house calibre 69355. IWC introduced this 41 mm generation in 2020 and it replaced the older 3714 series. A replica of this reference is a third-party watch that copies the dial, case, and branding. IWC does not make it and does not authorize it. The replica does not carry the calibre 69355.

Confirmed specs of the original

  • Case diameter: 41.0 mm
  • Case height: 13.0 mm
  • Movement: IWC calibre 69355, automatic, column wheel chronograph
  • Frequency: 28,800 vph (4 Hz)
  • Power reserve: 46 hours
  • Crystal: sapphire, front and caseback
  • Water resistance: 3 bar (30 m)
  • Strap: black alligator leather, steel pin buckle

US list price sits close to $8,000. IWC revises pricing by year and market, so check the current figure.

What a replica IW371615 is

Replica makers do not have the calibre 69355. Most builds use a Chinese automatic chronograph, such as a Valjoux 7750 clone, a Seagull movement, or another unit arranged to place the subdials at 12 and 6. Prices for this reference range from about $80 to $450. Higher tiers spend more on case finishing and dial print. None of them use an IWC movement.

Where replicas diverge from the original

  • Movement: the 69355 uses a column wheel and vertical clutch. Clone movements use a cam actuator. The pusher feel on start and stop is different.
  • Subdial spacing: the running seconds sits at 6 o'clock and the 30-minute counter sits at 12. Some replicas shift the center gap by a fraction of a millimeter.
  • Dial print: the letter spacing of IWC and SCHAFFHAUSEN. Replica strokes read thicker under 10x magnification.
  • Date window: the aperture at 3 o'clock. Replica edges are cut less cleanly.
  • Case finishing: brushed flanks and a polished bezel. Replicas often show wider brushed zones and softer lug edges.
  • Hands: leaf shape, rhodium plated. Replica hands can be brass with plating that wears at the tips.
  • Caseback: sapphire display back with engraved reference and serial numbers. Replica engraving cuts shallower.

Inspection points

  1. Measure the case with calipers at 3 and 9 o'clock. The original reads 41.0 mm.
  2. Run the chronograph for 30 minutes against a reference clock. The counter should track to the second.
  3. Compare the date font against photos of the reference.
  4. Weigh the watch. A light case suggests a plated alloy instead of steel.
  5. Check dial print under 10x magnification.
  6. Look at the caseback engraving under raking light.

Legal status in the United States

Counterfeit watches violate US trademark law. 18 U.S.C. § 2320 makes trafficking in counterfeit goods a federal offense, with a first-offense maximum of 10 years. 15 U.S.C. § 1114 covers civil infringement. US Customs and Border Protection can seize and destroy shipments at the border. Buying a replica for personal use differs from selling one, but the goods stay unlawful to traffic.

What the reference number tells you

IWC reference numbers are not serial numbers. IW371615 identifies the model, case material, dial color, and strap option. A seller who quotes the number without matching specs is describing a different watch. Verify the dial color, the strap type, and the case diameter against IWC's own listing before you compare any replica to it.