The IW371429 is an IWC Portugieser Chronograph reference. A replica of it copies a 40.9 mm chronograph with two subdials: small seconds at 6 o'clock and a chronograph minutes counter at 12 o'clock. Copies differ in case thickness, subdial spacing, dial print and movement. Ask a seller for measured thickness and clear photos of the caseback and pushers before you pay. I could not confirm the exact dial color and case metal that IWC assigned to IW371429, so check the number against IWC's own reference list first.
What the reference covers
The Portugieser Chronograph line uses reference numbers in the IW3714xx block. Each suffix marks a case metal and dial pairing. The base design is stable across the block: a round case, a domed sapphire crystal, applied Arabic numerals, feuille hands and a railroad minute track. IWC lists the current model at 40.9 mm across and 30 m of water resistance. The watch has no date window.
Specs to compare side by side
- Case diameter: 40.9 mm on the original. Measure the copy with a caliper.
- Case thickness: near 12.3 mm on the original. Many copies run 1 to 2 mm thicker.
- Subdial position: 12 and 6, vertical. Subdials set closer to the center point to a smaller movement.
- Chronograph function: the minute counter should advance in one-minute jumps and reset to zero with one push.
- Crystal: domed sapphire with a slight edge distortion at the rim. Flat glass is a sign of a cheaper build.
- Water resistance: the original is rated at 30 m. Treat any copy as splash resistant at best unless a test report comes with it.
What sits inside
The current original runs IWC calibre 69355, a self-winding chronograph with a 46-hour power reserve. Earlier versions used a modified Valjoux 7750 base. Replicas use a Chinese chronograph movement, often a Seagull ST19 hand-wound or a 7750 pattern automatic. A hand-wound copy will not match the original's rotor noise or power reserve. Ask which movement the seller ships and whether the chronograph runs on a module or a direct drive.
Checks before payment
- Ask for a photo of the caseback engraving at high resolution. Reference text should be crisp and centered.
- Request a video of the chronograph start, stop and reset. The minute counter must snap, not drag.
- Confirm the pusher feel. Mushy travel points to a low-grade module.
- Ask for the actual weight. A light case often means a plated alloy, not steel.
- Ask about the return window in writing. Photos hide dial print and hand finish.
Legal and practical note
Sale of counterfeit watches that carry a protected trademark is illegal in the US and the EU. Replicas sold as replicas still infringe trademarks when they copy logos and model names. Customs seizures are common on cross-border shipments. Resale value is close to zero, and no watchmaker will service a copy under a brand warranty. Buy with those limits in mind.