Short answer
A replica IW371408 is a copy of an IWC Portugieser Chronograph. The genuine reference sits in the IW3714 family, a line IWC built with a 40.9 mm steel case and the calibre 79350 chronograph movement. Copies match the outline of that watch. They differ in movement, case thickness, dial printing and caseback engraving. Dial colour and strap for IW371408 itself should be confirmed against a published reference list before any comparison, because IWC used the same case for many dial variants.
The genuine reference
IWC rated the IW3714 case at 40.9 mm across with 30 m water resistance. The dial carries applied numerals and feuille hands. Layout is bicompax: small seconds at 6 o'clock, chronograph minutes at 12. There is no chronograph hour counter. The movement is calibre 79350, a Valjoux 7750 base with 28,800 vibrations per hour and about 44 hours of power reserve. Subdial hands and the central chronograph hand sweep at that beat rate.
Where copies differ
- Movement. Many copies use an Asian 7750 clone, some use a quartz module, some use a hand-wind. A quartz copy shows a one-second jump in the small seconds hand. A mechanical copy beats at 4 Hz.
- Case depth. Clone movements and deeper casebacks add 1 mm to 2 mm of thickness on many units, so the back sits away from the wrist.
- Dial. Print weight, subdial ring depth, date window frame and numeral polish are the parts that show in photos taken at an angle.
- Hands. Feuille hands on copies run short at the tip or flat at the center. Genuine hands have a domed profile.
- Caseback text. Font, letter spacing and serial numbering are the fastest tell. Copies repeat the same serial across a batch.
- Strap. Most copies ship leather with an alligator print. Genuine straps use alligator skin, which needs CITES paperwork to cross borders.
Checks before you pay
- Ask for a photo of the caseback in daylight. Compare letter shape and spacing.
- Ask for a timegrapher reading: rate in seconds per day, amplitude in degrees, beat error in milliseconds.
- Measure case diameter and thickness with calipers if the watch is in hand. Target 40.9 mm.
- Press the chronograph pushers. Start, stop and reset should each feel firm and return to the same position.
- Compare subdial position against a photo of the genuine dial. Small seconds at 6, minutes at 12, both centered on the vertical axis.
- Check the crystal for anti-reflective coating on the inside face. A blue or purple cast under a lamp is the usual sign.
Price range
Copies sell from about $80 for quartz builds to $400 and up for units with a decorated 7750 clone and a sapphire crystal. Used genuine steel Portugieser Chronograph watches list in the thousands of dollars on resale sites. A seller offering a new watch at a copy price with a genuine box and papers is a mismatch worth noting.
Legal status in the US
Trafficking in counterfeit goods is a federal crime under 18 U.S.C. 2320. US Customs can seize shipments, and a seller who describes a copy as genuine commits fraud. Buyers of copies take on the risk of seizure and of receiving a watch with no service support.