What IW371747 refers to
IW371747 is a reference in the IWC Pilot's Watch Chronograph family. The base reference is IW3717, built from about 2006 to 2012. The digits after 3717 mark the case, dial, and strap combination. IWC used one 42 mm steel case across the line, so a single set of checks covers most of them.
Base numbers: 42 mm steel case, 14.8 mm thick, soft-iron inner case for magnetic protection, screw-in case back, sapphire crystal, water resistance rated to 60 m, caliber 79320 (a modified ETA/Valjoux 7750), 25 jewels, 28,800 vph, about 44 hours of power reserve. Dial layout: day and date at 3 o'clock, chronograph minutes at 12, chronograph hours at 6, running seconds at 9.
IWC reference lists do not show IW371747 in every catalog year. A seller who cannot name the dial color, case finish, and strap code is a seller to question.
Why this reference gets copied
The 7750 subdial layout matches a stock Valjoux movement, so a replica maker does not have to move the registers. The case shape is simple to machine. That makes the 3717 one of the easier IWC references to counterfeit and one of the harder ones to judge from photos alone.
Checks that separate a fake from a genuine watch
- Movement. Genuine 79320 rotors carry "IWC Probus Scafusia" engraving and a serial number. Most replicas use an unmarked 7750 clone or a quartz module. Ask for a photo of the movement through the case back.
- Case back. Genuine engraving is deep, sharp, and set in the correct font. Fake text is shallow, spaced wrong, or laser-etched with a gray tone.
- Dial print. "Schaffhausen" sits below the IWC logo. On fakes the type is thick and the letter spacing is uneven.
- Applied indices. Genuine markers are solid metal with beveled edges. Fakes use stamped or glued markers that sit above the dial surface.
- Date and day windows. Genuine windows are cut clean and the discs align at center. Fakes show gaps, fuzzy print, or discs that drift after a date change.
- Pushers and crown. Genuine pushers have firm, short travel. Replicas feel loose or gritty.
- Crystal and coating. Genuine sapphire carries an anti-reflective coating with a blue-violet tint under light. Cheap fakes have no coating or a heavy purple cast.
- Weight. A steel 3717 on a bracelet weighs about 170 g to 180 g. Most replicas run 20 g to 40 g lighter because the case and bracelet are thinner.
Price signals
Pre-owned genuine examples sell for about $4,000 to $6,500. Box and papers push a watch to the top of that range. Listings at $200 to $600 are replicas. Sellers who crop case back photos, refuse movement shots, or post stock images are the ones to skip.
What the search term means
People who type "fake iw371747" want one of two things: help checking a watch before a purchase, or a replica to buy. For the first group, a service quote from IWC or an independent watchmaker settles the question. Case back photos, a movement photo, and timegrapher results are the three items to request. For the second group, note the tradeoffs. Counterfeit watches carry no manufacturer warranty, run on movements with no official parts supply, and cannot be serviced by IWC. Resale value sits near zero.