The IW371431 is a stainless steel IWC Portugieser Chronograph from the 3714 family, and it is one of the most counterfeited Swiss chronographs sold online. A genuine watch has a 40.9 mm steel case, a caliber 79350 automatic chronograph movement, two subdials at 12 and 6 o'clock, and a date at 3. Most fakes expose themselves through a third subdial at 9 o'clock, a ticking seconds hand, or flat, shallow dial printing.
What is the IWC IW371431?
The IW371431 belongs to the Portugieser Chronograph line, a design defined by a clean dial, thin leaf hands, and applied indices. It is a dressy chronograph rather than a tool watch, which is part of why it is copied so heavily.
- Case: stainless steel, 40.9 mm wide, roughly 12.3 mm thick
- Movement: caliber 79350, automatic, 28,800 vph, 44-hour power reserve, 31 jewels, Valjoux 7750 base
- Dial: 30-minute counter at 12, running seconds at 6, date window at 3
- Crystal: domed sapphire with antireflective coating on both faces
- Water resistance: 3 bar, about 30 meters
- Strap: alligator leather on a steel pin buckle
Why is the IW371431 faked so often?
Its dial is simple, its case is a basic round steel shape, and the underlying chronograph architecture is widely available. That combination lets counterfeiters produce a passable-looking watch without solving complex case or dial geometry.
Demand also helps. The Portugieser Chronograph is one of IWC's best-selling references, so a fake has a large pool of buyers who may never have handled the genuine article.
How do you spot a fake IW371431?
What should the dial layout look like?
A genuine IW371431 has exactly two subdials and one date window. A counterfeit built on a standard 7750 layout often keeps three subdials, including one at 9 o'clock, which no 3714 reference ever had. If the subdial spacing crowds the date or the center of the dial, the watch is wrong.
How do the hands and printing look on a genuine watch?
Printing on a real dial is thin, sharp, and evenly spaced, with no bleeding into the silvered surface. Hands are polished to a mirror finish with clean bevels, and the running seconds hand at 6 o'clock sweeps smoothly through eight beats per second. A hand that jumps once per second is quartz, regardless of what the seller claims.
What does the movement tell you?
The 79350 is a modified 7750 with a signature rotor, striped bridges, and circular graining on the plates. Counterfeits usually hide an undecorated Asian 7750 clone or a quartz module under a printed rotor plate. A movement that cannot be seen, or that shows rough edges and misaligned screws, is a strong warning sign.
Does the caseback engraving matter?
Reference and serial numbers should be cut deeply and evenly, not lasered on the surface. The reference on a genuine piece reads IW371431, and the serial should match any paperwork or service records. Blurred text, uneven spacing, or a missing reference number points to a copy.
How should the case and crystal feel?
Steel finishing on a real Portugieser alternates crisp polished and brushed surfaces with defined edges. The sapphire crystal carries an antireflective coating on both sides, producing a faint blue tint at an angle. Genuine pushers have a firm detent and snap back on reset, while cheap copies feel mushy.
How do high-end replicas compare with cheap fakes?
Higher-tier replicas copy the two-subdial layout and use a decorated automatic chronograph, so they look closer at arm's length. They still fail on movement finish, crystal coating, engraving depth, and case weight. Budget fakes are usually quartz or use a three-subdial 7750, making them easy to identify in seconds.
How much does a real IW371431 cost versus a fake?
A pre-owned genuine Portugieser Chronograph typically trades in the low-to-mid four figures in US dollars, depending on condition, box, and papers. Counterfeits sell from around 150 to 700 dollars. A price far below market is the fastest single indicator of a fake.
Frequently asked questions
Is IW371431 a real IWC reference number?
Yes. It is a valid reference within the Portugieser Chronograph 3714 family and appears in IWC catalog and service documentation.
Can a jeweler authenticate an IW371431?
A watchmaker familiar with IWC can open the case, verify the caliber 79350, and check serials against factory records. Ask for that inspection in writing before you buy.
Do fakes ever use real IWC movements?
Almost never. Genuine 79350 movements are scarce and expensive, so counterfeiters use clones or quartz instead. Any seller claiming a real movement in a cheap watch is misrepresenting the product.