Top pick for most buyers: the replica IW371479 built on a modified A7750 chronograph with the running seconds relocated to 6 o'clock, a 40.9 mm stainless steel case brushed in the same direction as the original, and a sapphire crystal with anti-reflective coating on both faces. Three criteria decide whether a copy of this reference is worth owning: dial layout, case thickness, and movement finishing. Run all three before you pay, because the price gap between a good IW371479 replica and a poor one is small next to the quality gap.
What you are actually comparing against
The IW371479 sits in the 3714 family of the IWC Portuguese Chronograph. The layout has two subdials: a 30-minute counter at 12 and small running seconds at 6. There is no date window, the numerals are applied, and the hands are leaf shaped. The genuine watch measures about 40.9 mm across and roughly 12.3 mm thick, and it runs a heavily reworked Valjoux 7750, sold as IWC calibre 79350, with the seconds train moved to the bottom of the dial. Any replica that does not reproduce the 12 and 6 subdial positions fails at arm's length, so start there. Confirm the dial color and strap for your specific variant against the manufacturer's own reference data before you order.
Dial layout: the fastest tell
A stock 7750 places its subdials at 12, 9 and 6. Cheap IW371479 copies ship that way, which is why so many listing photos show a running seconds hand on the left side of the dial. A correct build uses a modified plate that drops the 9 o'clock register and moves the seconds to 6.
Pros of a corrected bicompax dial
- Subdial spacing matches the genuine at normal viewing distance
- Hands can be set to the proper leaf profile and length
- No date aperture, so there is no misaligned window to catch the eye
Cons
- Costs more than a stock 7750 build
- The relocated seconds train adds one more service point
Check print quality as well: brand text should be crisp and level, and the subdial rings should sit concentric with the hands. Ask for a straight-on macro shot with the chronograph stopped at zero.
Case profile and thickness
Case profile is where most replicas lose to the original. The genuine is a slim watch. A copy running a stock 7750 with a rotor spacer often measures 1 mm to 1.5 mm thicker because the movement sits deeper in the midcase, and that extra height changes how the watch sits under a cuff.
Pros of a thin, correctly profiled case
- Sits flat on the wrist and slides under a shirt sleeve
- Lug curvature and crown guards line up with the genuine silhouette
- Better balance on a leather strap, which is how this reference is normally worn
Cons
- Slimmer builds use thinner caseback gaskets and trade some water resistance
- Sellers rarely publish measured thickness, so you have to ask for caliper photos
Request a photo of the caseback on a caliper and a side profile shot against a ruler. Both are easy to fake with angles, so compare the crown height above the case too.
Movement: what to ask about
The genuine calibre beats at 28,800 vibrations per hour and carries roughly 44 hours of power reserve. Replicas use an A7750 or a clone of it, usually with decorative plates and a rotor engraved to resemble the original. Finishing quality varies more than timekeeping here.
Pros of the A7750 route
- Parts and servicing are widely available from independent watchmakers
- Chronograph function works and resets reliably when the movement is assembled well
- Push feel on the chronograph pushers is close to the original when the springs are correct
Cons
- Rotor noise and winding feel are audible compared with a finished Swiss calibre
- Decorated bridges can hide rough finishing underneath, so inspect before buying
Ask how the chronograph resets, whether the pushers have a firm stop, and whether the watch has been regulated. A seller who cannot answer any of those questions is not a seller worth using.
Crystal, caseback and strap hardware
The crystal should be sapphire with coating on both sides, which shows as a faint blue or purple sheen at an angle. Caseback engraving should be deep enough to catch a fingernail, not laser printed flat. On the strap, check stitching density, edge paint, and whether the buckle tang and pin are polished on the outer face only. Treat any water resistance claim on a replica as marketing. Do not swim with one regardless of what the listing says.
Pre-purchase checklist
- Subdials at 12 and 6, no register at 9
- No date window anywhere on the dial
- Measured thickness close to the genuine figure, confirmed with a photo
- Applied numerals sitting flush, not glued crooked
- Chronograph start, stop and reset tested on video
- Strap hardware and buckle finish shown up close
Which build suits which buyer
If you plan to wear the watch regularly, buy the corrected bicompax build with the slimmer case. The extra money goes into the two things people notice, which are the dial layout and the profile on the wrist. If the watch will live in a case and come out for photos, a stock 7750 version is a false economy because the subdial layout is the first thing a knowledgeable viewer spots.
Buyers on a tight budget are better served by a well-finished two-subdial build on a leather strap than by a thicker watch with a decorated movement nobody will see. Prioritize what shows.
Legal and practical note
A replica is not a genuine IWC watch. It carries no manufacturer warranty, no service history, and effectively no resale value. Customs authorities in the United States and elsewhere can seize counterfeit goods, and shipping carries that risk. Buy with that in mind, and treat the watch as a costume piece rather than an investment.