The replica IW371613 copies the IWC Portugieser Chronograph: a 41 mm stainless steel case, subdials at 12 and 6, a date window at 3, applied numerals, leaf hands, and a domed sapphire crystal. Three parts decide the quality of any copy: the case finishing, the dial print, and the chronograph movement inside. Everything else is trim.

What the IW371613 Reference Refers To

Watch brands use reference numbers to mark dial and case combinations inside one model line. The IW371613 sits in the Portugieser Chronograph family, so it shares the same 41 mm case and two-register layout as its siblings. Dial color, hand finish, and strap change between references; the case and movement do not.

Confirm the dial variant in the seller photos before you buy. Two watches in the same case can look very different at arm's length.

What a Replica Maker Has to Copy

The Portugieser Chronograph is a hard watch to fake well because the dial is clean. There is nowhere to hide sloppy printing.

• Case: 41 mm wide, about 13 mm thick, with a narrow bezel and straight lugs. The silhouette is the tell.
• Dial: applied Arabic numerals at 12 and 6, thin baton markers elsewhere, a 30-minute counter at 12, small running seconds at 6, and a date at 3. Feuille (leaf) hands.
• Crystal: domed sapphire with an anti-reflective coating, which makes the dial read almost black at steep angles.
• Movement: an in-house automatic chronograph calibre that replaced the older Valjoux 7750-based unit in the 2019 refresh.

Chronograph Movements in Replica IW371613 Watches

The movement is where most copies fail, and the reason comes down to subdial layout.

Why the Subdials Matter

A standard Asia 7750, which is a Valjoux 7750 clone, puts its counters at 12, 9, and 6, with running seconds at 9. The Portugieser needs minutes at 12, seconds at 6, and open space at 9. Makers solve that gap in three ways: a module bolted onto the 7750, a reversed movement, or a quartz setup that fakes the layout.

The Three Common Setups

1. Quartz fakes. The seconds hand ticks once per second and the chronograph pushers feel dead in the hand. Cheap, and easy to spot across a table.
2. Modified Asia 7750. Automatic, a real chronograph, and the correct subdial layout. Thicker than the original, and the rotor can rattle.
3. Decorated automatic. Same base as above, with a rotor and bridges engraved to suggest the original calibre. Look, not substance, but the case closes properly and the watch runs.

What Separates a Good Copy From a Bad One

• Lug curve. Good cases taper into the lugs. Bad ones leave a hard step where the strap meets the case.
• Dial print. The brand text and model name should stay sharp under a loupe, not fuzzy or doubled.
• Applied numerals. Polished on top, clean edges, no glue haze underneath.
• Date window. A crisp rectangle with a white disc and a font that matches the dial. Misaligned dates are common at the low end.
• Hands. Leaf shape, correct length so the tips reach the markers, consistent finish on both.
• Pushers. Firm clicks on start, stop, and reset. A mushy reset points to a worn or cheap movement.
• Strap and buckle. Many copies ship with stiff leather. Budget for a replacement strap.

Price Tiers for a Replica IW371613

Replica pricing tracks the movement and the case work, not the name on the dial.

• Under $150: quartz or a rough 7750, printed dial, mineral glass. Fine for a photo, poor on the wrist.
• $180 to $350: the value band. Sapphire crystal, a real automatic chronograph, and a decent dial.
• $400 and up: closer case profile, better finishing, decorated movement, usable strap.

Prices move with the market, so treat these ranges as guides rather than fixed numbers.

Size and Fit

The 41 mm case wears bigger than the number suggests because the dial runs edge to edge. On a 6.5 inch wrist it fills the top of the arm. On 7.5 inches it reads like a dress watch. Thickness near 13 mm means it can catch a shirt cuff, so see one in person if you can.

Checks to Run Before You Pay

1. Ask for a video of the chronograph running: start, stop, reset, and the counter snapping back to zero.
2. Request a straight-on dial shot and a profile shot in daylight. Side angles hide print flaws.
3. Confirm the crystal material in writing. Sapphire or nothing.
4. Check that the date flips at midnight and centers in the window.
5. Ask about the strap. If it is a cheap one, price a replacement into the deal.

FAQ

Does a replica IW371613 use a real chronograph movement?

Most automatic versions use a modified Asia 7750 with a swapped subdial layout. Quartz versions look similar in a photo, but the seconds hand ticks once per second.

Is the case size the same as the original?

Good copies match the 41 mm width. Thickness often runs 1 to 2 mm over because of the movement module stacked inside.

How do I test the subdials?

Start the chronograph and watch the 12 o'clock counter. It should jump once per minute. The 6 o'clock subdial should run as the seconds hand at all times.

What is the biggest giveaway?

Dial print and the date window. Both are cheap to fix and often left alone on low-end copies.

The Short Version

Buy the movement first, the dial second, and the strap last. A replica IW371613 with clean dial print, a working automatic chronograph, and a sapphire crystal covers most of the gap. Paying more than that buys small refinements, not a different watch.