A fake IW371752 is a replica of the IWC Portugieser Chronograph, one of the most copied dress chronographs you can buy. The real watch pairs a slim round steel case with a wide, uncluttered dial: two subdials, a date at 3 o'clock, leaf hands and a thin bezel. Replicas live or die on that dial, because the design leaves nowhere to hide. A crooked marker or a fat subdial hand shows up from across a table.
Short answer: the better replicas get the case and the dial close. What separates them from the genuine article is the movement, the printing under a loupe, and how the pushers and crown feel when you actually use them.
Why this reference gets copied so hard
The Portugieser Chronograph is simple in the best sense. Clean dial, applied numerals or markers, a case that sits flat on the wrist at roughly 41mm across and about 13mm thick. Nothing to distract the eye, which means every small flaw is exposed.
The genuine watch runs IWC's in-house calibre 69355, a column wheel chronograph with around 46 hours of reserve. Older versions of the same family used a modified Valjoux 7750, known inside IWC as the 79350. Replica makers rarely tool a movement from scratch. They buy a Chinese 7750 clone, decorate it, and engrave a rotor to look the part.
The three tiers you will run into
- Budget tier. Quartz or a rough 7750 inside a case that is a millimetre or two too thick. Subdials are printed rather than recessed, hand shapes are wrong, and the running seconds ticks once a second instead of sweeping.
- Mid tier. A working 7750 clone with decent dial print. The tells are in the details: shallow caseback engraving, hands a touch too thick, a date font that looks like a different typeface.
- Top tier. A decorated 7750 built to resemble the 69355 through the sapphire back, correct case proportions within a fraction of a millimetre, properly finished dial, and pushers with a real click rather than mush.
Dial tells
I start with the printing. On a genuine dial, the IWC wordmark and the "SCHAFFHAUSEN" line below it are crisp at 10x, with no ink bleed and even spacing. Replicas often use slightly bolder type, or the letters sit a hair too close together.
Next, the subdials. Chronograph minutes sit at 12, running seconds at 6. The hands should be flat, polished and shaped like a leaf, with a clean taper. On cheap fakes they look stamped, with rounded edges and a dull surface.
Then the date. The aperture should be cut square with a slight bevel, and the numeral should fill the window. A gap around the number, or a font that reads too wide, is a giveaway.
Case, crown and pushers
Look at the transition between brushed and polished surfaces on the lugs. Genuine cases have a sharp, deliberate line. Replicas tend to soften it, or polish the whole lug and skip the brushing.
Thickness matters more than people think. A 7750 based replica often runs 1mm to 2mm thicker than the real thing, which changes how the watch sits under a cuff. Put it on a flat surface and look at the profile from the side.
The pushers should start with a firm click and return with a snap. The crown should wind smoothly with no grit. That feel is hard to fake well, and it is usually where a cheap build shows itself.
Caseback and movement
Most versions of this reference have an exhibition back, so you get a free look at the movement. Compare the rotor engraving depth to reference photos. Thin, laser-etched text is a warning sign. Real engraving has depth and a slightly matte cut.
Check the balance wheel. A genuine 69355 has a free-sprung balance and a column wheel you can see when the chronograph runs. Clones usually show a standard cam and lever setup, plus a regulator arm.
Before you pay: a short checklist
- Ask for a video of the chronograph starting, stopping and resetting to zero.
- Request a straight-on dial shot, a macro of the printing, and a side profile.
- Confirm the case diameter and thickness in writing.
- Ask which movement is inside, and whether it is automatic with a sweeping seconds hand.
- Check the return policy before sending money.
What to expect, realistically
A good replica of this watch will pass a glance from a metre away. It will not pass a side-by-side comparison with the movement running and a loupe in hand. That is the honest trade. Buy from a seller who shows real photos of the actual piece, not factory renders, and expect to pay more for correct proportions and a movement that keeps time.
One last thing. If someone offers you a "genuine" IW371752 at a price that seems too good, run the checklist above in reverse. The tells that expose a fake are the same tells that expose a scam.