Short answer
A replica IW371484 is worth your money only if it copies three things: the 40.9 mm steel case, the two subdials stacked on a vertical line at 12 and 6 o'clock, and a running automatic chronograph movement with clean pusher action. Everything else, from strap stitching to caseback depth, is a detail you can replace or tolerate. Miss those three and no amount of polishing saves the watch.
Reference points to memorize
- Case: stainless steel, about 40.9 mm across, roughly 12.3 mm thick.
- Dial: two counters on a vertical axis, small seconds at 6, 30-minute totalizer at 12, date at 3.
- Movement: automatic chronograph, about 28,800 vibrations per hour, roughly 46 hours of reserve.
- Crystal: domed sapphire with anti-reflective coating on both faces.
- Strap: alligator-grain leather on a steel pin or folding buckle.
How to vet a replica IW371484 before you pay
- Measure the case with calipers. A correct copy reads 40.5 to 41.2 mm across the bezel and sits between 12 and 13 mm thick. Anything at 42 mm or thicker is a different watch wearing a Portugieser dial.
- Check the subdial axis. Hold the watch at eye level. The small seconds at 6 and the 30-minute counter at 12 must sit on one straight line through the center of the dial.
- Time the chronograph. Start it, run it ten minutes, then stop it. The counter at 12 should advance one tick each minute. Pass on any watch where that counter sweeps or the pushers grind.
- Inspect the date window at 3. The aperture should be crisp, the font thin and upright, and the date should snap over near midnight instead of drifting.
- Study the dial furniture under a loupe. Applied numerals and indices should be gold toned on the steel models and sit flush, with no glue haze around the feet.
- Tilt the crystal toward a lamp. Grade-A sapphire shows a faint blue or purple tint and almost no reflection. Mineral or plain glass looks milky at the edges.
- Flip the watch and read the caseback. Reference number, case material, and caliber should be laser etched or cut deep, not printed with a dot matrix look.
- Flex the strap. Alligator-grain leather should crease rather than crack, the stitching should run even, and the buckle engraving should match the case finish.
- Request a movement photo. A decorated rotor and perlage on the bridges separate a $180 quartz fake from a $400 automatic build.
Red flags
- Subdials placed at 3 and 9 instead of 12 and 6.
- A quartz movement sold as an automatic chronograph.
- Case width over 42 mm or a profile thicker than 13.5 mm.
- Bold, blocky date font that does not match the reference.
- A seller who will not send a photo or clip of the running chronograph.
Questions to ask before payment
- Which movement sits inside, and how many jewels does it carry?
- Is the crystal sapphire or mineral, and is the coating on one face or two?
- What is the measured thickness, not the listed thickness?
- Can the seller show the same watch on a timegrapher?
After it arrives
- Wind it fully and let it sit 24 hours to confirm the power reserve holds near spec.
- Reset the chronograph and check that both pushers return to zero without a jump.
- Treat water resistance as decorative. Never swim or shower with any replica.