What the IW371642 is

The IW371642 is an IWC Portugieser Chronograph. It belongs to the 41 mm steel Portugieser Chronograph line that IWC runs on calibre 69355, an in-house automatic chronograph with a column wheel. IWC gives each reference number its own dial, hand, and strap combination. Verify the dial and strap layout for IW371642 against the IWC catalog or the caseback engraving before you buy. If the seller cannot name the dial color and strap type, treat the listing as unconfirmed.

Genuine specs

  • Case: stainless steel, 41 mm across, about 13.1 mm thick
  • Lug width: 20 mm
  • Movement: IWC calibre 69355, automatic, column wheel, 4 Hz (28,800 vph)
  • Power reserve: 46 hours
  • Water resistance: 30 m
  • Crystal: sapphire front and back
  • Dial: two subdials. Running seconds at 6. Chronograph minutes at 12. Date at 3.
  • Strap: alligator leather, steel pin buckle or folding clasp

What replica versions use inside

No replica runs calibre 69355. Replica Portugieser Chronograph cases hold a Chinese automatic chronograph, in most cases a copy of the Valjoux 7750 architecture. That movement runs at 4 Hz with a 40 to 48 hour power reserve, so the numbers read close to the IWC spec.

Two differences show up in the hand. The 7750 stack is taller than the 69355, so replica cases run deeper. The 7750 uses a cam and lever for chronograph control, not a column wheel. The pushers need more force and the start feel is heavier.

Checks before you buy

  1. Subdial position. Genuine running seconds sit at 6 and chronograph minutes at 12. Many replicas keep the 7750 running-seconds hand at 9 or blank the subdial.
  2. Case thickness. Genuine is about 13.1 mm. Replica cases land at 13.5 mm to 14.5 mm.
  3. Caseback text. Reference number, serial, and caliber markings should match the case metal and edition.
  4. Weight. A steel 41 mm Portugieser Chronograph on leather is about 80 g to 90 g. A light case tub reads under that.
  5. Pusher feel. Column-wheel chronographs start with light pressure. Cam-and-lever movements do not.
  6. Date font and window. Replica date wheels use a wider font than IWC in many builds.

Price range

US retail for a steel Portugieser Chronograph on leather is near $8,000. Replica listings run $250 to $700. Case finishing improves above $500. No price in that range buys a column wheel.

What a replica cannot copy

The 69355 movement architecture, IWC finishing under the sapphire back, and factory service. IWC services its own calibres and supplies parts. Replica movements go to independent shops, or get replaced. Applied markers on the genuine dial are solid gold or rhodium plated and set into the dial. Replica markers are thin and glued.