The IW371620 is a reference in the IWC Portugieser Chronograph line. A replica sold under that number is a third-party copy of the watch. No copy uses the IWC calibre 69355. Most copies run a Seagull ST19 hand-wound movement or a reworked automatic 7750, and those two choices decide most of the differences you can see and feel.
What the reference is
The 3716 family arrived in 2020. IWC lists a 41 mm case, about 13 mm of height, and calibre 69355, an automatic chronograph with 46 hours of power reserve at 28,800 vibrations per hour. The dial is bicompax: a 30-minute counter at 12 o'clock and small seconds at 6 o'clock, with a date aperture at 3 o'clock on most variants. Hands are leaf shaped. Numerals are applied.
Reference numbers in the 3716 line split by dial color, case metal, and bracelet. This guide does not confirm the exact dial and metal of IW371620. Check the number on iwc.com before you compare a copy to factory photos.
What replica makers copy
- Case: 316L or 904L steel, 41 mm nominal. Measured samples run 41.5 mm to 42 mm.
- Dial: blue, silver, or black, with printed markers on cheap builds and applied markers on better ones.
- Movement: Seagull ST19 hand-wound at 21,600 vph, modified A7750 automatic at 28,800 vph, or quartz on the lowest tier.
- Crystal: sapphire. Anti-reflective coating on one face or both.
- Strap: alligator-embossed leather or a steel bracelet.
Checks before you buy
- Ask for the movement name and a photo with the caseback off. A rotor means automatic. No rotor means hand-wound.
- Ask for the measured case height. IWC is about 13 mm. Copies at 14 mm or more sit high on the wrist.
- Inspect the date window. Font, size, and position at 3 o'clock are frequent flaws.
- Check the subdial hands. They should reach the printed track at 12 and 6.
- Check the crown and pushers. Hand-wound ST19 builds feel different at the crown than automatic builds.
- Ask for a water resistance test record. Most sellers quote a number with no test behind it.
- Weigh the watch. Steel 41 mm chronographs land near 90 g to 110 g on leather.
Price bands
Quartz copies sell under $100. ST19 copies sit near $150 to $350. Modified automatic copies sit near $300 to $700. Dial color and bracelet choice move the price. Resale value on any replica is close to zero.
Limits
No copy matches calibre 69355. Movement finishing, rotor engraving, and the chronograph mechanism are absent or imitated. Service depends on the seller or an independent watchmaker who works on clone movements. Water resistance claims stay unverified without a test record. Counterfeit goods are seized by customs in many countries, and rules differ by market.
Short answer
Buy the movement you can name, measure the case, and verify the date window and subdials against factory photos. If a seller cannot name the movement or the caliber, treat the listing as unknown.