Buy the movement, the case, then the dial

Buy the movement, the case, and the dial in that order, and treat every other claim as marketing. A fake IW371418 that runs a genuine layout 7750 derived automatic, keeps the case at 40.9 mm with a 12.3 mm profile, and reproduces the silver plated dial's applied markers will pass at arm's length. One that misses any of those three will not, no matter how the listing is worded. Everything below is designed to help you sort the two apart before money changes hands.

The reference in one paragraph

The IW371418 sits inside the Portugieser Chronograph line: 40.9 mm stainless steel case, roughly 12.3 mm thick, 20 mm lugs, silver plated dial with gold toned leaf hands and applied numerals, a 30 minute counter at 12, small seconds at 6, and a date window at 3 on most variants. Water resistance is rated at 3 bar, which is splash resistance, not swimming. The movement is the IWC 79350, a Valjoux 7750 base. Memorize those numbers and check each one against the watch in front of you.

What to look for

Movement

Ask for a photo of the movement with the caseback removed and a short video of the chronograph starting, stopping, and resetting. A 7750 derived automatic shows the wobble of an oscillating weight when the watch is rocked, and the pushers have a firm mechanical click instead of a mushy travel. Quartz fakes hide behind closed casebacks and vague claims about never needing a battery. Watch the small seconds at 6 as well: a 28,800 vph movement sweeps smoothly, while a quartz subdial ticks once per second and exposes the whole watch.

Case and finishing

Measure it. 40.9 mm across, with lug to lug near 47 mm. Genuine brushing runs one direction on the case flanks with polished bevels on the lugs. A weak fake shows rounded lug edges, uneven brushing, or a crown sitting proud of the case band. The crown should be signed, with crisp fluting and no tool marks on the caseback notches.

Dial printing and hands

Under a loupe or a phone macro lens, printing should be flat and sharp. Inspect the double dot at 12, the thin strokes of the numerals, and the date window. A poorly cut aperture with a white plastic date ring is a giveaway. The leaf hands should be gold toned, with a mirror polish on the top facet and a matte flank, and the subdial hands should reach the track rather than stopping short.

Strap and buckle

Most IW371418 examples ship on black alligator with a pin buckle. Strap quality is the cheapest thing for a seller to upgrade, so never let a nice strap carry a weak watch head.

Parameter bands to accept or reject

  • Case diameter: 40.7 to 41.1 mm. Outside that range the proportions read wrong on the wrist.
  • Thickness: 12.0 to 12.6 mm. Much thinner almost always means a quartz movement.
  • Lug width: 20 mm.
  • Movement: automatic, 7750 derived, 28,800 vph preferred.
  • Crystal: sapphire, with anti reflective coating on the inside surface.
  • Water resistance in practice: treat any replica as splash resistant only.

Pitfalls that cost the most

  • "Swiss made" on the dial carries no weight. It is printed, not earned.
  • QC photos that skip the date window, the subdial hands, or the caseback.
  • Listings mixing photos of two different watches. Ask for one timestamped set.
  • Gold plating sold as solid gold. A loupe settles that argument quickly.
  • No service path. Many independent watchmakers decline replica work, and a broken 7750 clone becomes a paperweight.
  • Customs risk. Counterfeit watches can be seized at import, and you may lose both the watch and your money.

Legal and practical reality

Counterfeit watches infringe trademarks and are illegal to import into the United States and most of Europe. Buying one is a personal risk decision, not a loophole. If you proceed, understand that you have no warranty, no manufacturer service, and no recourse when the watch arrives wrong. A local watchmaker may refuse to open it at all.

FAQ

Is IW371418 the same as the 3714 line?

Yes. 371418 is one reference inside the broader 3714 Portugieser Chronograph family, which is why dial colors, hands, and case metals vary across the range. Match the exact reference before comparing photos.

Can a fake pass a jeweler's inspection?

Rarely under a loupe. Case finishing, date font, and movement decoration are the three areas that trip up replicas most often.

Does a replica hold water resistance?

Assume no. Gaskets and caseback sealing on a replica are not tested to the original's 3 bar rating, so keep it away from water.

Should I pay more for a "1:1 Swiss" replica?

That tier language is unregulated. Spend on documented movement quality and accurate dimensions, not on a label a seller invented.

What kills resale value?

Everything. Replicas have no collector market, no service records, and no authentication path.