Quick answer
A fake Portugieser Automatic 42 is a replica of IWC's 42mm Portugieser Automatic, usually modeled on the ref. 5007 generation. The good ones copy the case size, the dial layout, the hands and the strap. What none of them copy is the movement: the genuine watch runs IWC's in-house calibre with Pellaton winding and a seven day power reserve. If a replica's power reserve indicator actually tracks the running time, that is the exception rather than the norm.
What the genuine watch is
The Portugieser Automatic 42 measures 42.3mm across, with small seconds at 9 o'clock, a power reserve arc at 3, and a date window at 6. Leaf hands, applied Arabic numerals, a railway minute track, sapphire front and back, and an alligator strap. The ref. 5007 runs the 52010 calibre with a 168 hour reserve. It is a clean, legible design, and most of what people recognize from across a table is proportion, not detail.
Where replicas land close
- Case diameter. 42mm replicas are easy to make and most sit within a fraction of a millimeter.
- Dial layout. Small seconds, reserve arc and date window are usually placed correctly.
- Strap and buckle. Alligator-grain leather and a signed pin buckle are standard at every tier.
- Crystal. The better tiers use sapphire with workable anti-reflective coating.
Where they fall apart
- The movement. No Pellaton winding, no seven day reserve. Expect 38 to 45 hours and a rotor you can hear across a quiet room.
- The reserve indicator. Often decorative, fixed in one position, or driven off the wrong gear train.
- Case finishing. The brushed-to-polished transitions on the case sides go soft, while the genuine stays crisp.
- Dial print. The spacing of the brand text and "Automatic" drifts under magnification.
- Hands. Leaf hands come out thicker near the base, or polished to a different grain.
- Weight. A plated case never matches the heft of solid gold, and it wears through at the lugs.
What I check first
- Ask for a movement photo. Decorated bridges are fine, as long as you know what sits underneath.
- Wind it fully, note the time, and see whether the reserve indicator follows the actual run down.
- Time it in three positions over 24 hours. Replicas typically drift 10 to 30 seconds a day.
- Look at the profile from the side. The Portugieser has a thin bezel over a tall case band, and replicas often flatten that step.
- Check date centering at 6 o'clock. Crooked dates are the most common tell.
Price tiers
Under $150 buys a generic 42mm case with a printed dial and a disposable movement. Between $250 and $450 is where the passable ones live. Above $600 you are paying for a movement clone and better case work, and at that point the gap to a used genuine gets uncomfortable.
The legal side, plainly
In the United States, trafficking in counterfeit goods is a federal offense and customs can seize shipments, including personal orders. Buying is lower risk than selling, but reselling opens you to criminal exposure and civil claims from the trademark owner. That is worth knowing before a $400 watch turns into a letter.