Short answer
A replica IW371632 is a third-party copy of the IWC Portugieser Chronograph. The genuine watch is a 41 mm stainless steel chronograph with a two-register dial, a date at 3 o'clock, and IWC calibre 69355 inside. A copy can match that outline from arm's length. What separates a decent copy from a bad one is the dial printing, the subdial positions, the crystal coating, and whether the chronograph actually runs. Spend your budget on the movement first and the cosmetics second.
What the reference is
IW371632 sits inside the Portugieser Chronograph family, a line IWC has built in several dial and strap variations. The design language stays consistent: a wide, thin bezel, leaf-shaped hands, applied markers on some versions, and open dial space around the subdials. That open space is where copies fail, because a spacing error is visible from across a table.
One warning before anything else. The word replica covers two different products. A homage carries its own brand name and is legal to sell. A true replica prints the IWC name on the dial and infringes the trademark. Price, legal exposure, and resale value differ between the two, so identify which one is on the table first.
Prerequisites
- A digital caliper accurate to 0.1 mm.
- A phone with macro mode, or a 10x jeweler's loupe.
- A straight-on photo of the genuine reference from an official source for scale comparison.
- A realistic budget band, from quartz copies at the bottom to clone-movement copies at the top.
Step-by-step checks
- Measure the case diameter across the bezel with the caliper and note the figure. The target for this reference is 41.0 mm.
- Measure the lug-to-lug span and the case thickness, then compare both against the published figures for IW371632.
- Photograph the dial straight down, then scale it to match the genuine photo and overlay the two.
- Compare the two subdials: equal diameter, centered on the vertical axis, and matching finish.
- Press the upper pusher to start the chronograph and watch the central seconds hand for lag or stutter.
- Press the lower pusher to stop and reset, then confirm the hand snaps back to 12 with no offset.
- Inspect the date window at 3 o'clock under the loupe. Look for square cutout edges, a matching font, and no white border showing through.
- Read the dial text at a low angle. Check for level baselines, even stroke weight, and no ink bleed.
- Tilt the crystal under a lamp and check the anti-reflective tint. A strong purple or blue sheen is common on cheap sapphire.
- Turn the watch over and check the caseback engraving for depth, crispness, and correct spelling of the reference number.
- Unscrew the crown and cycle through each setting position, listening for a clean click at every stop.
- Weigh the watch on a kitchen scale and read the number alongside the strap material.
Movement types you will meet
Three tiers show up in this reference. At the bottom is quartz, which keeps time but gives you a dead chronograph or a sweeping seconds hand that ticks once per second. In the middle is a generic automatic chronograph module, often with the subdials in the wrong places. At the top is a clone of the IWC 69355 architecture, which is the only tier where the pusher feel, the subdial layout, and the winding action come close to the real thing. Movement quality drives the price more than any other single factor.
Red flags
- Case diameter off by more than 0.5 mm from the listed figure.
- Subdials sitting too far apart or drifting off the vertical center line.
- Chronograph seconds hand that starts with a visible jump.
- Date font that is heavier or wider than the genuine printing.
- Caseback text that is shallow, uneven, or misspelled.
- Crown that grinds or refuses to screw down flush.
Care and expectations
A copy of this reference will not hold value and will not be serviced by IWC or an authorized watchmaker. Parts for clone movements come from the same aftermarket supply as the watch itself. Keep it away from water even if the caseback claims a depth rating, because the gaskets on most copies are untested. Wipe the case with a soft cloth, keep the leather strap dry, and treat any chronograph fault as a reason to stop pressing the pushers rather than to force a reset.
Bottom line
Judge a replica IW371632 on measurements, not on marketing photos. Verify the 41 mm case, the subdial alignment, the chronograph function, and the dial printing before you judge the finish. If the movement tier is unclear, the price will usually tell you which one you are looking at.