Start with the seller, not the watch
Before you pay for a fake IW545173, demand macro photos and a short video of the exact unit you will receive. The listing image tells you nothing. What matters is the dial printing at 10x magnification, the height of the sub-seconds hand, the depth of the caseback engraving, and the movement finishing behind the display back. Ask for caliper readings of diameter and thickness, a side-profile shot of the crown, and a clip of the watch running. A seller who cannot produce these is reselling a factory photo, and the watch you open will not match it.
The reference sits in IWC's Portuguese line, a hand-wound family with a large round case, applied numerals, leaf hands, small seconds at six, and a sapphire display back. Confirm the exact dial variant against official press images first, because the same reference number has appeared with more than one dial finish, and a replica compared against the wrong photo will always look wrong.
What to look for on this reference
Case and proportions
The Portuguese is a dress watch with a wide dial and a slim bezel, so thickness is where replicas fail. A case that is a millimeter or two too deep sits high on the wrist and looks wrong in profile. Check the lug curve, the polished chamfer along the caseband, and the crown size. An oversized or undersized crown is an instant tell at arm's length.
Dial and applied numerals
Numerals should be raised, faceted, and polished on their top surface. Flat stamped numerals with rounded edges read as cheap. Printing should be sharp with no ink bleed, and the minute track should sit close to the rehaut. The small seconds subdial should be recessed with a finish that matches the genuine, either snailed or smooth. Look at the spacing between the subdial and the six o'clock marker, since this is a common error.
Hands
Leaf hands should reach the minute track without touching it. Check that the hour and minute hands are the same finish, that the blued tone is consistent across both, and that the sub-seconds hand is thin and properly counterweighted. Sloppy hand-setting shows as uneven height between the hands and the dial.
Caseback and movement
A hand-wound watch should show a hand-wound movement. Through the display back you want a plate layout that matches the genuine, engraved lettering with crisp edges, blued screws set flush, and stripes that run in one direction. Reject any watch with a glued decorative plate over a quartz or automatic movement, and be suspicious of jewel counts printed on the rotor bridge that do not match the visible jewels.
Strap and buckle
Genuine-grade straps use alligator with visible scale structure, not embossed cowhide. Check the stitching density, the tang shape, and the engraving depth on the buckle. A stamped buckle is a cost signal that usually extends to the rest of the watch.
Parameter bands worth measuring
- Diameter: within 0.3 mm of the published spec, measured across the bezel.
- Thickness: within 0.5 mm. Anything a full millimeter over spec is a different case.
- Lug width: confirm against the reference, commonly 22 mm on this family.
- Crystal: sapphire, slightly domed, anti-reflective coating on the inside face only.
- Weight: within a few grams of the reference on a comparable strap.
- Water resistance: treat every depth claim as unverified unless the caseback gasket and crown seal are shown.
How the tiers differ
Budget replicas cut corners on the case, using mineral glass, printed rather than applied numerals, and a rough winding feel. Mid-tier pieces add sapphire and better dial work but often keep a movement that only looks correct from two feet away. Top-tier builds pay for case machining, correct thickness, hand-finished dial furniture, and a movement whose layout survives close inspection. Your money buys case work and dial work, not the badge.
Common pitfalls
- Listings that reuse factory photos across several sellers and never show the actual serial area.
- Claims of Swiss origin on a watch with an unmarked Asian movement.
- Subdial spacing that crowds the six o'clock marker.
- Casebacks with shallow laser engraving instead of deep stamping or engraving.
- Sapphire advertised but mineral glass delivered, easy to test with a drop of water or a scratch test on an inconspicuous edge.
- Sellers who refuse video, refuse caliper readings, or push for payment outside a protected channel.
FAQ
Is a fake IW545173 worth buying at all?
Only if you accept that it is a replica with no service history and no warranty. Buy it as a costume piece and judge it on case finish and dial accuracy, not on resale value.
Can I tell the difference on the wrist?
Thickness and dial printing are the two giveaways at conversation distance. Anyone who handles watches will notice a deep case before they notice a logo.
Should the movement be hand-wound?
Yes. An automatic movement in a hand-wound reference is a structural error, and the caseback view will expose it.
What is the single best check?
A caliper reading of thickness taken on the actual unit, followed by a macro photo of the dial printing. Those two answer most of the questions.
Pre-purchase checklist
- Match the dial variant to official images of the reference.
- Request caliper photos of diameter and thickness.
- Request a 10x macro of the dial, numerals, and subdial.
- Request a clear photo of the movement through the caseback.
- Confirm crystal material and coating in writing.
- Pay through a channel with buyer protection, and inspect on arrival before removing any protective film.