The short answer
The IW371476 is a Portugieser Chronograph with a white lacquered dial and blued hands, and any replica of it stands or falls on the dial. Get the 41 mm case proportions, the recessed subdials at 12 and 6, and the deep flat blue of the hands right, and you have a watch that reads correctly on the wrist. Miss those and no amount of decorated rotor engraving saves it. A cheap build gives itself away through printed subdial rings, purple-tinted hands, and a case that sits a millimeter too thick.
What this reference is, and why factories copy it
IW371476 belongs to the Portugieser Chronograph line that IWC restyled with the Edition 150 Years look: stainless steel, 41 mm across, white lacquered dial, blued steel hands and appliqués, two registers, small seconds at 6, chronograph minutes at 12, date at 3. Inside the genuine piece is IWC's in-house caliber 69355, an automatic with about 46 hours of power reserve. Earlier 3714 references used a modified Valjoux 7750, IWC's caliber 79350, and that history is the reason so many replicas of this watch run on 7750 architecture. If the listing you are reading cites a slightly different sub-reference, the checks below still apply. The dial layout, case shape, and strap are shared across the family.
Dial and hands: where the tells live
The real dial is lacquered, so it has a wet gloss and a soft step where the lacquer meets the outer edge. Good replicas use a lacquered or at least a properly glossed disc. Budget ones use flat white paint that looks chalky under a phone light.
- Hands: real blued steel is a deep, even navy that shifts a little with the light. Painted or ion-plated hands read purple, or they look flat with a visible seam at the base.
- Subdials: both registers should sit recessed with a fine concentric texture, not as printed rings laid on top of the dial.
- Date: the window should be crisp, the disc white to match the dial, and the font close to IWC's. A chunky date font is one of the fastest ways to spot a budget build.
- Printing: the IWC and SCHAFFHAUSEN text should be sharp and level. Check the spacing to the subdials and the position of the minute track.
- Hand length: the chronograph seconds hand should reach the minute track. Short or oversized hands look wrong from a few feet away.
Movement: what is really in there
Most replicas of this reference run an Asian 7750 with cosmetic work: a decorated rotor, blued screws, and sometimes a plate shaped to mimic the 69355 layout. A few higher-tier builds use a clone laid out with a column wheel for appearance. Either way, the practical tests are simple. Start the chronograph, let it run a minute, reset it, and watch whether the hand snaps back to zero. Push the pushers and feel for grit or slack. On a genuine 69355 the action is crisp. On a cheap 7750 it feels soft and vague.
Listen as well. A 7750-based rotor can be loud. Ask for a video of the watch running, not just a wrist shot.
Case, crystal, and thickness
The genuine case is 41 mm wide with 20 mm lugs and a thickness just over 13 mm. Replicas built on a 7750 often add a millimeter or more, which changes how the watch sits under a cuff. Ask the seller for a caliper photo. The crystal matters too. The original is sapphire with anti-reflective coating on both faces, so it nearly disappears at an angle. Copies with coating only on the outside show a blue or green haze, and uncoated glass reads as a pale mirror.
Case finishing should show brushed flanks and polished bevels meeting in a clean line. Run a fingernail along that transition. A sloppy polish rounds it off.
Strap and hardware
Match the strap to the blue of the hands rather than to the heaviest saturation in the listing photos. Look at the stitching, the padding, and the buckle engraving. A thin stamped buckle with shallow markings is common on budget builds. If the strap feels like cardboard, plan on a replacement before you wear it.
Questions worth asking before you pay
- Which movement is inside, and can you send a photo of the caseback and rotor?
- What is the measured case thickness with calipers?
- Are the hands blued steel or plated?
- Does the chronograph reset to zero, and does the date change without sticking?
- What is the return policy if the dial finish is not as shown?
Red flags
Listings that never show the dial straight on. No movement photo. Claims of Swiss made on a watch that clearly uses an Asian chronograph. A price far under the rest of the market. Sellers who will not confirm thickness or answer a question about the date font. Any single one of those is reason enough to walk away.
One last practical note: check what your country allows for import, and treat any replica as splash-resistant at best no matter what the listing says.