A "fake IW371704" is a counterfeit of the IWC Pilot's Watch Chronograph reference IW371704, the 43mm steel "Le Petit Prince" edition with a blue dial. If you are holding one and want a quick read, start in three places: the movement visible through the caseback, the dial printing under a loupe, and the engraving on the back. Almost every replica of this reference slips on at least one of them.

What the genuine reference actually is

IW371704 sits in the 3717 family of Pilot's Watch Chronographs. Steel case, roughly 43mm across, blue dial, white printed markings, applied numerals filled with lume, and a day-date window at 3 o'clock. The layout is three registers: chronograph minutes at 12, chronograph hours at 6, and running seconds at 9. Inside is the IWC caliber 79320, a heavily reworked Valjoux 7750 base, and the case carries a soft-iron inner cage for magnetic protection. That cage is why the caseback sits deeper than you might expect on a watch this size.

Where replicas fall apart

Dial and printing

Look at the "IWC" wordmark and "Schaffhausen" line at 12. On the real thing the type is crisp and evenly spaced. On replicas the letterforms get fat, the spacing drifts, and the text often sits a hair off center. The subdial rings are another tell. Genuine subdial tracks are thin and sharp. Repainted ones look muddy under magnification, and the hands on the small registers can be the wrong length.

Case and finishing

Genuine IWC brushing runs in one direction and stays consistent around the lugs. Replicas show uneven brush lines, soft lug edges, and polished surfaces that look cloudy rather than mirror-bright. Pusher action is the giveaway nobody fakes well. Real chronograph pushers have a firm, short travel and a clean reset snap.

Movement

Pop the back, or look at photos of the back. A genuine 79320 shows IWC's own finishing and rotor engraving. Most replicas run a stock 7750 clone with rough perlage, cheap screws, and a rotor marked with the wrong text or no text at all. The movement is also where the subdial spacing comes from. A clone 7750 forces the registers to sit closer together than the genuine dial allows, and you can see that in photos if you compare the gaps.

Caseback and serial

Reference and serial numbers are engraved, not printed, and the depth is even. Fakes use shallow laser etching that catches light differently. Cross-check the serial against the reference. If the number comes from a run of another model, walk away.

Checking one before you buy

• Ask for a close, straight-on shot of the dial and one of the caseback with the serial.
• Ask for a photo of the movement with the rotor turned so you can see the bridges.
• Compare dial proportions against the official product images for the reference.
• Have a watchmaker open it. A movement inspection costs little next to the price of a bad buy.
• Treat any price far under market as the answer to your question.

The legal side

Counterfeit watches are illegal to import and sell in the United States, and seizures happen at the border. Buying one knowingly carries risk beyond losing money. If the goal is the look of a pilot chronograph on a budget, there are honest alternatives from other brands that cost less than a convincing fake and hold value better.