The best fake IW371480 you can buy today is the high grade clone built around a Valjoux 7750 derived chronograph movement, the tier that matches the genuine 40.9 mm steel case, the silver plated dial, and a working two register chronograph. I compared the tiers sold now on four points: case size and profile, dial and hand finishing, movement type with a functioning chronograph, and how the watch reads on the wrist next to the real Portugieser Chronograph.

What the real IW371480 actually is

IWC built the IW371480 as a stainless steel Portugieser Chronograph. The case measures 40.9 mm across, the dial is silver plated with gold plated hands and applied numerals, and the strap is black alligator. Inside sits the calibre 79350, a chronograph movement that traces back to the Valjoux 7750 family.

That movement detail drives everything in this guide. It sets the case height, the pusher feel, and the register layout that every copy has to imitate. The layout is two registers: chronograph minutes at 12 o'clock and running seconds at 6. There is no 12 hour counter and no small seconds at 9, which is one of the first things a knowledgeable eye checks.

Tier 1: High grade 7750 based clone

This is the tier that matches the reference on the measurements that matter, and it is the one I would pick for daily wear.

Pros:

  • Case close to the genuine 40.9 mm with the correct lug curve and a mix of polished and brushed surfaces
  • Automatic 7750 based movement with a chronograph that starts, stops, and resets with a firm pusher click
  • Recessed subdial rings, applied numerals, and leaf shaped hands that hold up under a loupe
  • Domed sapphire crystal with an anti reflective coating on the front

Cons:

  • Usually a millimetre or two thicker than the original because of the movement stack
  • Dial text spacing and subdial ring thickness vary between batches, so photos matter
  • The strap is alligator grain leather, not actual alligator, and it is the first part worth replacing

Use case: someone who wants the closest wearable match, wears the watch often, and expects people to look at it from close range.

Tier 2: Mid grade 7750 clone

Same movement family, less attention paid to the surface work.

Pros:

  • Mechanical chronograph function is preserved, so the pusher feel and the sweeping hand still behave correctly
  • Lower outlay than the top tier for a similar overall silhouette
  • Still fits standard 20 mm straps, so upgrading the band is easy

Cons:

  • Dial printing is softer and the subdial rings sit flatter under light
  • Hands may be painted gold tone rather than gold plated, which dulls over time
  • Bezel thickness and case finishing can drift from the reference by a visible margin

Use case: a budget conscious buyer who wants a mechanical chronograph on the wrist and is not chasing side by side accuracy.

Tier 3: Quartz and faux chronograph copies

The cheapest category, and the one that gives itself away fastest.

Pros:

  • Low cost, light on the wrist, and no winding or servicing to think about
  • Fine as a knockaround piece for travel or messy work

Cons:

  • The 6 o'clock subdial is often a battery seconds hand that ticks once per second, which no mechanical watch does
  • Pushers may be decorative or drive a chronograph hand that jumps in one second steps
  • Gold tone plating wears through at the crown and lugs, and the case weight feels hollow
  • Case size frequently runs larger than the real 40.9 mm

Use case: only if you want a cheap beater and have no interest in it passing as the real watch.

Criterion: case size, thickness, and lug shape

Start here, because the case is what someone notices before the dial. Ask the seller for the diameter and the thickness measured with calipers, not the listing text. Watch the lug tips: on the genuine watch they curve down and hug the wrist, while cheaper cases sit flat and leave a gap. If the case is much over 41 mm or noticeably thick, the watch will look wrong on a small wrist.

Criterion: dial, hands, and crystal

The silver plated dial should change tone as you tilt it, not stay flat white. Subdial rings should be slightly recessed, and the printed text should stay sharp at arm's length. Check the hands: gold plated leaf hands catch light along the bevel, while painted hands look chalky. On the crystal, a faint blue or purple reflection is normal; a heavy mirror tint is not.

Criterion: movement and chronograph function

Request a short video of the chronograph running. You want to see the center hand start smoothly, the 12 o'clock minute counter advance in small increments, and the reset snap back to zero. A 7750 based automatic winds with a rotor you can hear, and the caseback should show a decorated movement rather than a blank plate. If the seller cannot produce that video, walk away.

Bottom line

Pick the high grade 7750 based clone if accuracy matters and you plan to wear the watch regularly. Drop to the mid tier if the budget is tight but you still want a mechanical chronograph with correct behaviour. Skip the quartz tier unless you are buying a disposable beater, because the ticking subdial and the flat dial are the two details that end the conversation.