What Is the IW371748?

The IW371748 is a reference in the IWC Portugieser Chronograph family, a 41 mm stainless steel chronograph with a bicompax dial, two subdials, and a display caseback. The line has been in continuous production since the late 1990s and sits among IWC's best known models. A fake IW371748 is any watch that copies this reference but was not produced by IWC Schaffhausen.

Why Is This Reference Faked So Often?

The Portugieser Chronograph has a clean, symmetrical dial with applied numerals and a simple round case. Those are exactly the features counterfeiters find easiest to copy convincingly from a photo. Strong demand plus a five-figure retail price creates the margin that makes the effort worthwhile.

Most fakes survive a glance at arm's length and fail the moment someone opens the caseback.

How Do You Spot a Fake IW371748?

Dial printing and subdials

Genuine dials carry crisp, slightly raised printing with sharp serifs and evenly spaced rail tracks around both subdials. Fakes usually show fuzzy edges, heavy ink, and subdial rings that sit a fraction off center.

Applied numerals and hands

Real applied markers are polished on every visible face and sit flat against the dial. Counterfeit markers are often plated, subtly domed, or bedded in visible glue haze.

Case finishing

Study the border between brushed and polished surfaces. An authentic Portugieser case shows a hard, consistent line around the lugs, while fake cases look soft from over-polishing or casting.

Crown and pushers

Genuine chronograph pushers engage with a short, firm click and return cleanly. Fake pushers feel spongy, wobble, and frequently sit at mismatched heights.

Crystal and coating

IWC sapphire carries a faint blue-violet anti-reflective tint with almost no distortion at the edges. Cheap replicas use mineral glass or uncoated sapphire that glares under light and warps the outer dial.

Caseback engraving

Factory engraving is deep, uniform, and machine-cut, and the reference and serial match the paperwork. Fake engraving is shallow and laser-etched, and the lettering often varies in depth across the same line.

How Does the Movement Give a Fake Away?

The fastest single test is to open the caseback. IWC finishes its calibers with branded bridges, defined bevels, and engraved plates that generic movements do not replicate.

Note that some older Portugieser Chronographs used a 7750-family base, so the base architecture alone proves nothing. The tells are the finish, the engraving, and the presence of IWC markings where the maker expects them.

Chronograph Function Test

Start the chronograph and watch the central seconds hand. A correctly built caliber starts with a clean snap, sweeps evenly, and lands exactly at twelve when reset. Counterfeit movements often drift on reset, stutter during the sweep, or jump the moment the pusher is pressed.

Do Boxes, Papers, and Serials Prove Authenticity?

Not on their own. Fake boxes and printed cards are cheap to produce, and many counterfeit listings include them to build false confidence. IWC serials are engraved on the caseback and on the movement of most references, and they should match each other and the documentation.

What Should a Real One Cost?

Pre-owned Portugieser Chronographs generally trade in the mid four figures in US dollars, varying by dial variant, production year, and completeness. A listing asking a few hundred dollars for a steel automatic chronograph is offering a counterfeit, whatever the photographs show.

Frequently Asked Questions

Is a fake IW371748 worth buying?

A counterfeit comes with no manufacturer warranty, no parts support, and no resale market. US Customs and Border Protection can seize counterfeit goods at import, which leaves the buyer with nothing.

Can a jeweler identify a fake IW371748?

Yes. Any competent watchmaker can identify the movement family within seconds of opening the caseback, and case and dial finishing confirms it.

Can the reference number itself be wrong?

Frequently. Replica listings often blend digits or drop the IW prefix, so verify the exact reference against IWC's own archive before judging the watch.