The short answer
A replica of the IWC reference IW545189 is judged mostly by its dial and its case profile. The design comes out of IWC's Portugieser family, which is a study in restraint: a large flat dial, thin printed text, applied markers, and a slim polished bezel. There is nowhere for sloppy work to hide. If the printing is thick, the markers sit at the wrong height, or the case measures two millimeters wider than it should, the watch reads as a copy from across a table.
Dial and printing
Look at the minute track first. On the real dial it is a hairline of even weight, and it meets the markers without a gap. Replicas tend to print heavy and let the track blur at the inner edge. The brand name and the model text should be crisp, with correct letter spacing. Subdials, where the version has them, need to sit on their axis and stay no larger than the original.
Hands matter as much as the dial. The Portugieser uses leaf shaped hands with a fine point and a polished bevel, and the finish should catch light along the whole length. Painted hands with a flat sheen are an easy tell. On most versions there is no lume at all, so a dial that glows in the dark is wrong.
Case, crystal, and proportions
Ask for measured numbers instead of the seller's claim. Most Portugieser references sit between 40 and 42 mm across and stay under about 14 mm thick, counting the crystal. A case that comes in at 44 mm, or rides 16 mm off the wrist, is a different watch wearing the same dial. Check the lugs as well: they should taper and curve down, with sharp edges where the polished flank meets the brushed side.
Sapphire should be clear with a faint blue or colorless anti reflective coating, not the heavy purple tint that cheap crystals carry. The bezel is polished and narrow, and any step or gap between it and the case is a defect.
Movement and caseback
IWC builds this line around its own automatic calibres, finished with Geneva stripes, a signed rotor, and engraved bridges. Through a display back you should see clean perlage, blued screws, and a rotor with the brand marking cut rather than stamped. Most replicas use a decorated Asian automatic that looks convincing in photos and less so in hand, or a hand wound copy with no rotor at all. The caseback engraving is worth reading too. Reference and serial numbers should be cut deep and clean, and the font should match IWC's house style.
Strap, buckle, and crown
The strap is alligator or alligator embossed leather in dark brown, black, or blue, with a matching stitch line. Check the buckle stamp and the crown marking, which is one of the smallest details and one of the most faked. A crown that feels gritty when winding or setting points to a cheap movement, whatever the dial says.
Tells that give a copy away
- Thick fuzzy printing, and a minute track that runs into the markers.
- A date window with the wrong font, or a date sitting off center.
- Lume on a dial that should not have any.
- Case thickness over about 14 mm, or a case wider than 42 mm.
- A rotor that rattles, and a caseback engraving that looks laser etched.
Questions worth asking before you buy
- What is the measured case diameter and thickness with the crystal?
- Which movement is inside, and does it hand wind and hack?
- Is the crystal sapphire with anti reflective coating on both sides?
- Are the photos of the actual watch, including a straight on dial shot and a caseback shot?
- What is the return window if the watch does not match the listing?
A final note: a replica is a replica. It will not hold value, service like an IWC, or survive a close look under a loupe. If what you want is the look on the wrist for a fraction of the price, the checklist above is how you avoid the worst of the market.