Short answer: a replica IW371618 can look convincing on the wrist because the Portugieser Chronograph is a simple, flat dial with two subdials and almost no clutter. That same simplicity is what exposes a bad copy. There is nowhere to hide a sloppy print job or a thick case. Buy the version that gets the case profile and the dial printing right, and skip the ones that only nail the color.
What the genuine watch is
The IW371618 sits in the IWC Portugieser Chronograph family, the 3716 series introduced with the in-house calibre 69355. That means a 41mm steel case, a column-wheel chronograph, about 46 hours of power reserve, sapphire on both sides, and 30 meters of water resistance. The dial has a small seconds hand at 6 and a 30-minute counter at 12, with no date window. If a seller shows you a date at 3, you are looking at a different reference or a fantasy dial.
IWC builds several dial variants inside the 3716 range, so confirm the exact dial and strap combination for your reference against the brand's own page before you compare anything. A rep that is accurate to one variant is wrong for another.
Where replicas usually win
Case shape is the easy part. The Portugieser is a round, thin-bezel case with long lugs, and most mid-tier factories cut it well. The applied numerals and the leaf hands also come out clean on the better runs, because they are simple stamped and polished parts. Get a good example and the silhouette reads correctly from a few feet away.
Where replicas usually lose
- Dial printing. The rail track and the "IWC" wordmark should be thin and crisp. On cheap copies the text looks bold and slightly fuzzy under a loupe.
- Subdial finish. The two counters have a fine snailed texture. Flat, smooth subdials are a giveaway.
- Thickness. The genuine watch is around 13mm. Many replicas run 13.5 to 14.5mm because of the movement, which changes how the watch sits under a cuff.
- Caseback. This watch has an exhibition back, so the movement is on display. Look for clean perlage, blued screws, and correct engraving depth. Rep rotors often have shallow, machine-looking text.
- Pushers. Press the chrono start and stop. It should feel firm with a defined click, not mushy or gritty.
Movement choices
Most replicas of this reference use a modified Valjoux 7750 style movement or a Chinese chronograph with a decorated bridge. The 7750 layout pushes the subdials to roughly the right spots, which is why the dial reads correctly. A handful of higher-end builds use a clone of the 69355 with a column wheel. Ask which movement is inside and whether the chronograph resets to zero cleanly. That single test tells you more than any photo.
Price tiers, roughly
Entry replicas run a few hundred dollars and usually show fat printing and a thick case. Mid-tier builds fix the dial and the case profile. The top tier costs several times more and focuses on movement finishing and pusher feel. Past a certain point you are paying for the back of the watch, not the front.
A quick checklist before you pay
- Confirm the reference's real dial color and strap.
- Ask for a straight-on dial photo and a profile photo.
- Check the subdial positions against the genuine layout.
- Ask for a video of the chronograph starting, stopping, and resetting.
- Check the caseback engraving and the movement finish.
- Confirm the return policy in writing.
The honest summary: this is one of the easier references to copy well, and one of the easier ones to spot when it is copied badly. Spend your money on dial printing and case thickness, not on packaging.