Quick Answer
A replica IW371670 is a third-party copy of the IWC Portugieser Chronograph, a 41mm stainless steel watch with a bi-compax dial and the in-house 69355 automatic chronograph calibre. It is not produced, authorized or warrantied by IWC. Replica quality varies widely, so the useful question is not whether a replica IW371670 exists, but which movement and finishing standard a given example uses.
What the Genuine IW371670 Is
The reference belongs to the Portugieser Chronograph line, which IWC has produced across several generations. The 3716 family introduced the in-house 69355 calibre in place of the older modular chronograph used in the 3714 generation. The design language stays consistent: a clean round case, a slim bezel, applied Arabic numerals and a vertically arranged pair of subdials.
- Case: stainless steel, approximately 41mm across
- Dial layout: bi-compax with running seconds at 6 o'clock and chronograph minutes at 12 o'clock
- Movement: IWC 69355, automatic, roughly 46 hours of power reserve
- Crystal: sapphire with anti-reflective treatment
- Water resistance: 30 meters, which is splash resistance rather than swimming resistance
- Strap: leather with a pin or folding buckle depending on the variant
Because the genuine watch is a chronograph with a specific subdial arrangement, a replica has to solve a real mechanical problem rather than simply copy a case shape.
How Replica Versions Differ
Replica IW371670 watches fall into three broad groups, and the movement is the main dividing line.
- Quartz copies. Low cost, often with frozen or decorative subdials. The seconds hand ticks once per second instead of sweeping.
- Automatic chronograph builds. Commonly based on an Asian 7750 or a similar automatic chronograph movement. The chronograph works, but the subdial layout does not match the genuine watch without modification.
- High-tier builds. Better case finishing, closer dial printing, a modified or cloned movement, and sometimes a decorated rotor and bridges.
The layout issue matters. A standard 7750 places its subdials at 12, 6 and 9, while the Portugieser uses only 12 and 6. Builders either blank the 9 o'clock position, add a module, or use a movement with the correct configuration. Ask which solution was used, because it affects both how the dial looks and how the watch behaves.
What to Check Before You Buy
Inspect these points in order. They separate a wearable replica from a disappointing one.
- Subdial function. The 6 o'clock subdial should run continuously as small seconds. The 12 o'clock subdial should count chronograph minutes.
- Chronograph reset. Start, stop and reset the chronograph several times. Hands should snap back to zero, not drift.
- Hand alignment. Check that the subdial hands and the center chronograph seconds hand line up with the markers at zero.
- Dial printing. Look at the font weight of the brand text, the spacing of the rail track, and whether the numerals sit evenly.
- Crystal. Sapphire with an anti-reflective coating looks clear; mineral glass tends to show more glare and scratches sooner.
- Crown and pushers. Winding and setting should feel smooth, with no grinding and no excessive play.
- Caseback. Engraving depth and lettering quality are a reliable signal of overall build care.
- Size and weight. A 41mm case should sit like a 41mm case. Odd proportions usually mean a generic case was used.
Movement Options in Detail
Most automatic replica IW371670 watches use one of a few movement families.
- Asian 7750. Robust and widely serviced, but the rotor is often audible, and the subdial layout is wrong unless modified.
- Modified 7750 with a module or a blanked subdial. Closer to the genuine dial, though overall thickness can increase.
- Cloned or decorated 69355. Looks closer under a display back, and the layout is often correct. Long-term parts availability is the trade-off.
- Seagull-based chronographs. A different architecture with a different reliability profile, sometimes seen in mid-tier builds.
The genuine 3716 shows its movement through a sapphire caseback, so this detail is visible on many replica builds as well. For a watch with a solid caseback, decoration matters less than function. For a display back, it matters a great deal.
Price Tiers and What You Get
Price tracks the movement and the finishing, not the name on the dial. Entry tiers use quartz or basic automatic movements with stamped cases and printed dials. Mid tiers add a working automatic chronograph, a sapphire crystal and cleaner printing. Top tiers invest in case polishing, better dials, and a movement that sits closer to the 69355 in layout and appearance. Moving up a tier mostly buys better dial detail and smoother chronograph action rather than a completely different watch.
Practical and Legal Notes
A replica is not the genuine article, carries no IWC warranty, and should never be sold or represented as an original. Servicing is also a practical concern, since many watchmakers decline replica work and sourcing parts can be difficult. If a seller claims a replica is "1:1" or "identical", treat that as marketing language rather than a specification. Compare the actual movement, the subdial behavior and the finishing instead.
Bottom Line
A replica IW371670 can be a reasonable visual stand-in for the Portugieser Chronograph when the movement layout is correct and the finishing is careful. Judge it on the chronograph function, the subdial positions and the dial printing. Those three checks will tell you more than any seller description.