Quick answer
A replica IW371620 is worth considering only when the case measures 41 mm across, the dial keeps the 12 and 6 subdial layout, and the chronograph resets cleanly to zero. Check those three points first. Everything else, from printing sharpness to caseback engraving, is a grading detail that separates a mid-tier copy from a top-tier one.
Prerequisites
- The genuine reference numbers for the IWC Portugieser Chronograph 41 mm: case diameter, thickness, lug width, and movement caliber.
- A digital caliper that reads to 0.1 mm.
- A 10x loupe or a phone macro lens.
- Photos of the exact unit you are buying, not a stock catalog image.
How to evaluate the replica
- Write down the genuine baseline. The current Portugieser Chronograph runs 41 mm wide, about 13 mm thick, with a 20 mm lug width, an in-house 69355 column-wheel chronograph, a 30-minute counter at 12 o'clock, small seconds at 6, and sapphire crystals front and back.
- Measure the case with the caliper at the bezel edge and across the lugs. A copy that reads 40 mm or 42.5 mm is built on a generic case, not a reference-matched one.
- Check dial symmetry with a straight edge. The 12 and 6 subdials should sit on one vertical axis, and the outer minute track should be evenly spaced from the rehaut all the way around.
- Examine the printing under the loupe. Look at the wordmark, the numerals, and the rail track. Genuine-standard printing is crisp with no ink bleed, no bolder strokes on one side, and no filled-in counters on small numerals.
- Compare hand finish. The feuille hands should taper to a sharp point, and the leaf shape should be symmetric on both halves. Blunt tips or uneven lume fill indicate a low-grade dial.
- Run the chronograph. Start it, let it run 60 seconds against a reference clock, stop it, and reset it five times. The sweep should be smooth, and the reset should snap back to zero without drift or hesitation.
- Inspect the caseback. Look for the sapphire window, the reference engraving depth, and the serial font. Engraving that looks laser-etched and shallow is a common weak point.
- Weigh the watch and check the strap. A steel chronograph on leather in this size should feel substantial. Look at stitch density, edge paint, and whether the buckle tang aligns with the holes.
- Ask for a short video of the seconds hand and the chronograph reset. Static photos hide stutter, and stutter is the fastest way to spot a cheap quartz or poorly regulated automatic.
Red flags
- Subdials that sit lower or higher than the genuine layout, or a 6 o'clock subdial that is a 12-hour register instead of small seconds.
- Pushers that feel gritty or need force to engage.
- Casebacks screwed on with visible gaps or a misaligned engraving.
- Sellers who will not send photos or video of the actual unit.
- Any claim that the watch is genuine. A replica is a replica, and pricing should reflect that.
Legal and practical note
Counterfeit goods are restricted in most markets, and US customs can seize shipments. Treat this guide as an inspection checklist for disclosed replica pieces, and keep purchase records.
Sizing and wear
The 41 mm case wears large on wrists under 6.5 inches because the Portugieser has thin bezels and a wide dial opening. Try a 20 mm strap on your wrist before you commit, and confirm the replica accepts standard 20 mm aftermarket straps. If it does not, the lugs are cut to a non-standard width and the case is not worth the money.