A fake IW371493 is a copy of the IWC Portugieser Chronograph, the 40.9mm steel watch with two subdials at 12 and 6 and IWC's 79350 movement inside. Most replicas nail the silhouette from three feet away. What they rarely nail is the crystal coating, the caseback engraving, the dial print under a loupe, and the feel of the pushers. Those four things decide whether you are holding a decent replica or something being passed off as the real watch.
What the genuine reference actually is
IW371493 sits inside the 3714-generation Portugieser Chronograph family, so it shares the architecture with every other steel reference in that line. You get a 40.9mm stainless case at roughly 12.3mm thick, 30m of water resistance, and sapphire glass with anti-reflective coating on both faces. The dial has applied numerals, feuille hands, a chronograph minute counter at 12, running seconds at 6, and no date window. Inside is calibre 79350, an IWC rework of the Valjoux 7750 base running at 28,800 vph with about 44 hours of reserve.
That layout matters. If the watch in front of you has a date at 3, or the subdials sit at 9 and 3, it is not a 3714 case at all no matter what the seller says.
Tells that survive a wrist check
- Crystal. The real one has double-sided AR coating, so it nearly vanishes and shows a faint blue or purple sheen at an angle. Cheap copies use uncoated glass that flares under a lamp.
- Caseback engraving. Reference and serial numbers on a genuine caseback are laser-cut with even depth and clean edges. Fakes often look sandblasted or slightly rounded.
- Pushers. A 7750-based chrono should start with a firm, defined click. Mushy pushers or a stuttering chrono hand usually mean a cheap module or quartz inside.
- Dial print. Look at the spacing between the IWC mark and the Schaffhausen line, the polish on each numeral, and the crispness of the subdial rings. Copies tend to fatten the numerals and flatten the rings.
- Hands. Feuille hands taper to a fine point. Copies are blunt at the tip and thicker through the middle.
- Strap and buckle. Signed pin buckle, real alligator scale structure, tight and consistent stitching.
- Case finishing. The brushed and polished transitions should be sharp and separate, not washed together by a soft polish.
The movement is the line in the sand
Ask for a photo of the caseback off, or a short video of the chrono running. If the movement is a decorated clone with no markings that match IWC's finish standards, you are looking at a replica. If someone refuses to show it, that answers the question too. On a genuine 79350 you should see the rotor engraving, Geneva-style striping, and blued screws sitting flush.
What I would ask a seller
- Can you photograph the movement with the caseback removed?
- Is the reference number engraved or stamped, and does it read IW371493 exactly?
- Does the crystal have AR coating on both sides?
- Do you have service papers or an IWC extract?
- Why is the price where it is?
Price and honesty
Steel Portugieser Chronographs trade in the mid four figures on the used market. A "new in box" IW371493 at a fraction of that is a replica, not a bargain. A replica sold as genuine is fraud, full stop, no matter how close the copy gets. If you want a replica for what it is, that is your call. Just never pay genuine money for one, and never let it leave your hands described as the real thing.