The fastest answer: treat any watch offered as an IW545132 as unverified until a watchmaker has the movement and the caseback engraving in hand, because those two elements are the hardest to copy at cost and the easiest to fake in a photograph. That movement-and-caseback inspection is the top pick, and it beats every other test in this guide. The checks below are ranked on five criteria: how hard the detail is to copy, how much of it you can see in photos, what it costs to verify, how much it tells you about the rest of the watch, and whether the finding holds up under a second opinion.

What the reference number IW545132 does and does not tell you

A reference number is a model-family identifier, not a serial number. One reference can cover several watches that differ in case metal, dial colour or strap, and the same number should never be treated as proof of origin on its own. IWC groups its references in blocks, and the block a number falls into tells you which family of watches you are looking at: case size, hand-wound or automatic, and the general style of the dial. A listing that leans on the number and shows nothing else gives you nothing to verify.

Before you spend money, ask the seller for the full reference as engraved inside the caseback, the case number, and a photo of both. Then confirm that pairing with IWC or an authorised dealer. If the reference cannot be matched to a catalogued configuration, stop there.

Pros

• Free, fast, and done before any money changes hands.
• A mismatched reference or case number is an instant walk-away signal.

Cons

• Brands do not publish a complete public lookup table, so verification means contacting a dealer or service centre.
• Sellers in the replica market use reference numbers loosely, so a correct number still proves nothing about authenticity.

Check one: movement and caseback engraving

On a hand-wound watch in this family you are looking at a slow-beating, hand-wound calibre with visible finishing. Expect Geneva stripes on the bridges, circular graining on the base plate, blued or polished screw heads seated flush, and a signed bridge or balance cock. Winding feel matters too: a hand-wound movement should wind with even resistance from the first turn to the last, without grinding or a sudden soft spot.

The caseback is where careless work shows. Engraving on a genuine watch is cut deep and even, the letterforms match across every line, and the reference and case numbers sit in a fixed relationship to the hallmarks and the brand mark. Compare screw slot widths, caseback thread quality, and the crispness of the edge where the caseback meets the mid-case.

Pros

• This is the hardest check to pass with a cheap movement, and the most decisive.
• Finishing and engraving quality carry across the whole watch.

Cons

• Requires a watchmaker, and a case opened carelessly can lose its water resistance.
• Higher-end replicas fit decorated generic movements, so judge the style of the finishing, not the presence of stripes.

Check two: dial, hands, and crystal

Dial printing on a real watch is flat and sharp, with no ink bleed into the lacquer and no ragged edges on the minute track. Applied indices should have polished facets that flash as you tilt the watch, and the hands should carry bevels along their length with no tool marks on the tops. On models with a subdial, the printed rings sit concentric with the hand pivot. The crystal should be sapphire, with anti-reflective coating that leaves a faint colour cast at an angle and no visible distortion across the dial.

Pros

• Visible in ordinary photos, so you can screen a listing before travelling.
• Applies to every example of the reference, not just one seller.

Cons

• Photos are lit and retouched for the sale, and dial flaws vanish at low resolution.
• A well-made replica dial passes at arm's length, so this check never settles the question alone.

Check three: case, crown, lugs, and strap

Look for clean transitions between polished and brushed surfaces, with the brushed grain running one direction and no rounding on the lug edges. The crown should be signed, seat squarely against the case, and feel positive in every position. Straps should show even stitching, matched keepers, and a buckle with crisp engraving rather than a soft stamp.

Pros

• Case lines and crown feel are hard to hide once you hold the watch.
• Poor refinishing is a common tell on watches sold as untouched originals.

Cons

• Genuine watches get polished too, which blurs the same lines you are checking.
• Straps and buckles are swapped often and say little about the watch head.

Check four: the listing, the price, and the paperwork

A price far below the market for the reference, stock photos instead of the actual watch, refusal to show the movement, and pressure to pay outside a protected method are the four patterns that repeat across bad listings. Papers and boxes help, but they are also copied, so treat them as supporting evidence rather than proof.

Pros

• Costs nothing and filters out most bad deals in minutes.

Cons

• Honest private sellers sometimes have no papers, so a missing box is not proof of anything.

Which route fits your use case

If you are buying as a collector, buy the watch head through an authorised dealer or a specialist who can show service records and will put the reference and case number in writing. If what you want is the look on a budget, buy a replica that is sold openly as a replica, from a seller who prices it as one and offers returns. The risk sits in the middle: a watch presented as genuine at a replica price. Selling counterfeit goods as genuine is illegal in the United States, and you have little recourse if you pay for one. A replica sold as a replica is a known quantity, a fake sold as the real thing is a loss.