Short answer
A replica IW371628 is a counterfeit copy of an IWC Portugieser Chronograph. The reference number belongs to a genuine watch sold through IWC boutiques and authorized dealers. Copies of it are produced in unlicensed factories, mostly in China, and sold through direct-to-consumer websites and social media sellers. Buying one means accepting trademark risk, no factory service, no parts supply, and almost no resale value. The reference number in a listing is a marketing device, not a specification you can rely on.
What the IW371628 actually is
The IW371628 sits inside IWC's Portugieser Chronograph family, a two-register chronograph with a clean, high-contrast dial and a strap that dominates the silhouette. Within that family the details change by reference: case metal, dial color, hands, and strap material all vary. Because counterfeiters reuse reference numbers across generations, the only dependable source for the exact build of IW371628 is IWC's own product listing and an authorized service center. Treat any seller spec sheet as unverified until it matches those records.
Why this reference gets copied
Portugieser Chronograph copies are common for practical reasons. The dial layout is simple and photographs well from any angle, which makes cheap listings look convincing online. The strap hides case finishing flaws that would be obvious on a bracelet. The chronograph function gives the copy a mechanical story to sell, even when the movement inside is a generic module that shares nothing with the original. The result is a watch that looks plausible in a photo and behaves differently the moment it is handled.
Legal position in the United States
Counterfeit watches infringe registered trademarks. U.S. Customs and Border Protection can seize counterfeit shipments, and ordering for personal use does not create a personal-use exemption. Selling copies is a separate and more serious matter than owning one, and trafficking in counterfeit goods can carry criminal exposure. Buyers who resell a copy to fund an upgrade are the ones most likely to end up with a problem they did not plan for.
Service and ownership reality
IWC services its own watches and will not service a counterfeit. That sounds obvious until a copy stops running. A general watchmaker may be able to open it, but a generic chronograph module inside a copy often has no standardized parts chain, so a repair can cost more than the watch did. Water resistance claimed in a listing is usually untested and frequently imaginary. Resale is equally thin: no authorized dealer, auction house, or reputable pre-owned platform will take one.
How to confirm a genuine example
- Take the watch to an IWC boutique or authorized service center.
- Ask them to confirm the reference and serial number against factory records.
- Request a service estimate in writing, which forces an inspection of the movement.
- Compare the returned documentation against the papers supplied at purchase.
Buy only from an authorized dealer or a pre-owned dealer who provides that verification trail in advance. If a seller resists the process, the answer is already in the resistance.
A lower-risk path to the same look
The Portugieser Chronograph reads as a dress chronograph: slim, legible, and quiet. A stainless steel chronograph from a mid-tier Swiss or Japanese brand delivers that presence with a real warranty, real service, and a resale market. That route costs more than a copy today and costs far less over the years you own it.