Short answer
A fake IW371485 is a copy of IWC's Portugieser Chronograph in stainless steel. The genuine watch is a 40.9 mm steel chronograph with a 30-minute counter at 12 o'clock, running seconds at 6, and the date at 3. Replicas of this reference run from about $80 in quartz up to $400 and beyond for versions built on a modified Valjoux 7750. The subdial layout is what separates a wearable copy from a toy. Get that right and the watch reads correctly from across a table.
What the real reference is
The IW371485 sits in the 3714 Portugieser Chronograph family. That means a 40.9 mm polished and brushed steel case, roughly 12.3 mm thick, a domed sapphire crystal over the dial, a sapphire display back, and 3 bar of water resistance. Inside is IWC calibre 79350, a heavily reworked Valjoux 7750 running at 28,800 vph with about 44 hours of power reserve.
One detail matters more than any other. IWC reworked the chronograph so elapsed minutes sit at 12 and running seconds sit at 6. There is no 12-hour totalizer. That is unusual for a 7750 base, which normally puts running seconds at 9 and a 12-hour counter at 6. The reference suffix, the last digits after IW3714, tells you which dial, hands and strap IWC paired with that steel case, so check the official catalog photo for your exact combination before comparing anything.
Where replicas give themselves away
- Subdial layout and spacing. Cheap copies keep the stock 7750 layout and print the dial to match, so the small seconds end up at 9 instead of 6. In photos this is the fastest tell.
- Stuttering seconds. Moving running seconds to 6 requires indirect gearing. On many replicas the hand ticks in small jumps instead of sweeping. On the genuine calibre it glides.
- Date window. Check the aperture shape, its distance from the dial edge, and the numeral font. Replicas often use a generic font and sit the window too far inward.
- Caseback engraving. Reference numbers, IWC Schaffhausen lettering and the Probus Scafusia mark should be crisp and evenly spaced. Blurry laser etching shows up fast under a loupe.
- Crown and pushers. The chrono pushers should have a firm, defined click. Start, stop and reset should feel mechanical. Mushy pushers or a reset that jumps usually mean a cheap module underneath.
- Hands and printing. Leaf-shaped hour and minute hands should be polished with sharp edges. Thick paint, flat finishing, or misaligned printing stands out under magnification.
- Strap and buckle. Genuine pieces ship on alligator with a signed steel pin buckle or deployant. Replicas often arrive with stiff embossed leather and an unsigned buckle.
Movement tiers
Quartz versions are the bottom rung. They keep time and little else, and the chrono pushers usually feel like buttons on a remote.
The mid tier uses an Asian 7750 with the dial printed to mimic the IWC layout. If the seconds hand sits at 9, the layout was never corrected and the watch is not trying very hard.
The top tier uses a 7750 with transfer gearing or a clone movement that genuinely places seconds at 6. These are the copies worth owning. Ask for a video of the watch running, with the chrono started and reset, before you pay. You are listening for a clean sweep and a reset that snaps back to zero without wandering.
Questions to ask a seller
- Are these photos of the actual watch, or stock images?
- Which movement is inside, and does the running seconds hand sit at 6?
- Can you send a short video with the chronograph running?
- What is the actual case diameter measured with calipers?
- Is the strap leather or alligator, and is the buckle signed?
Owning one
Treat the water resistance as decoration. 3 bar is splash protection at best, and on a replica you should assume less. Keep the pushers away from water entirely. The 7750 base is a robust design and any competent watchmaker can service it, though parts for the decorated IWC-style finish may not be available.
Strap choice changes the look more than anything else. A matte black or dark brown alligator with a signed buckle gets you most of the way there, and it costs far less than chasing a better case.