A fake IW371770 is a replica of the IWC Portugieser chronograph sold under that reference, and you can judge one in about five minutes by checking four things: dial printing, case profile, pusher action, and movement. IWC builds this watch as a two-register chronograph with a wide, open dial, so a copy has nowhere to hide a mistake. Most replicas fail on proportion or on the movement, not on the logo.
Reference codes carry real information. IWC uses the last two digits of a reference to point to dial, hands, and strap combinations, not to a different watch, so an IW371770 describes one exact look. Pull up a photo of that reference first, or you may end up judging a copy against the wrong dial color.
What does the IW371770 reference cover?
The genuine watch is a Portugieser chronograph: two subdials, a slim bezel, leaf-shaped hands, and applied Arabic numerals on a silvered or colored dial. Any copy that adds a date window where the reference has none, or shifts the subdial spacing, is a different watch wearing the same number.
This matters for buyers because sellers mix references. A replica listed as IW371770 but built from a generic Portugieser case and a blue dial is not the same watch as the reference you looked up. Compare the photo, the dial color, and the strap type before you compare finishing.
Which details separate a good fake IW371770 from a bad one?
Four areas carry most of the evidence. Work through them in order, since the cheap tells sit on the outside and the costly ones sit inside the case.
Dial and hands
Print sharpness is the first test. Genuine IWC dial text sits crisp under a loupe, with even stroke weight on the brand line and no ink bleed at the edges. Copies show fuzzy edges, uneven letter spacing, or text that sits too thick.
Check the subdials next. The concentric texture should catch light in a smooth gradient, and the hands should reach the track without overhang. Replica subdial hands run short or flat, and the pinion caps can sit proud of the dial.
Case, lugs, and pushers
Case finishing separates price tiers more than any other part. Real Portugieser cases carry a mix of polished and brushed surfaces with sharp, consistent transitions. Replicas round those transitions off because hand polishing costs time.
Press the pushers. A chronograph start-stop pusher should feel firm with a short, clean travel, and reset should snap back with no drag on the minute counter. A soft or gritty pusher points to a cheap 7750 clone or a quartz module behind a fake dial layout.
Movement and caseback
Steel Portugieser chronographs vary: some show the movement through sapphire, others close the back with steel. If you can see the movement, look for decoration that makes sense, correct engraving depth, and a rotor that spins without wobble.
Older genuine watches used a modified Valjoux 7750 base, and newer ones use IWC's in-house 69000-family calibre. A replica showing a stock 7750 with a stamped plate and no real perlage will not pass a close look, though it can still keep good time.
Strap, buckle, and clasp
IWC straps use tight stitching, firm edge paint, and a signed tang or deployant. Replica straps feel thinner in the hand, the stitching wanders, and the logo engraving on the buckle is shallow.
What do the price tiers buy?
- Under $150: quartz movement, printed subdials that do not work, hollow lugs, and mineral glass. The watch tells time, but the chronograph is decoration.
- $250 to $600: Asian 7750 clone, working chronograph, sapphire crystal, and a case with decent brushing. This is the tier where most buyers land.
- $700 and up: cleaner dial printing, closer case proportions, decorated movements, and sometimes a column-wheel clone. Gains are small and price jumps are large.
Price tracks finishing, not accuracy. A $300 copy and a $900 copy can both keep good time, so pay for the details you can see on the wrist: dial text, case edges, and pusher feel.
How should you inspect a fake before paying?
- Match the watch to a photo of the exact IW371770 reference, including dial color and strap.
- Measure the case with calipers and compare it to IWC's published dimensions for that reference.
- Wind it, start the chronograph, let it run ten minutes, then reset and confirm both hands return to zero.
- Check the crown: hand-winding should feel smooth, with no grinding and no wobble in the stem.
- Shoot a macro photo of the dial with your phone and zoom in on the printing and the subdial edges.
- Ask the seller to name the base movement. A seller who cannot say whether it is a 7750 clone or something else is a risk.
Is buying a fake IW371770 legal?
Selling a counterfeit as a genuine watch is illegal in the US and most of Europe, and US Customs can seize counterfeit imports. Watches sold as replicas sit in a different legal space, but the risk of seizure and the lack of any warranty stay with the buyer.
Service is the practical question at this price. Independent watchmakers will work on a standard 7750 clone because parts are easy to source. Many will not touch a counterfeit with a branded dial and caseback.
FAQ
How much should a fake IW371770 cost?
Expect $250 to $600 for a working chronograph with sapphire glass and a decent case. Below $150 you are buying quartz with decorative subdials, and above $700 you pay for finishing, not for a better movement.
Can you spot a fake IW371770 from photos alone?
Often, yes. Dial print, subdial spacing, and case edge sharpness all show up in a good macro shot. Pusher feel, winding smoothness, and movement finish need the watch in hand.
Will a watchmaker service a fake IW371770?
Some will, if the movement is a common 7750 clone and parts are available. Others refuse counterfeit watches as a rule, so ask before you buy if long-term service matters to you.