The IW371698 is a Portugieser Chronograph variant from IWC, and the tell on any replica of it comes down to proportion rather than branding. If the case is 41 mm wide, about 13 mm thick, and the dial runs a 30-minute counter at 12 with small seconds at 6, the watch reads correctly across a table. If the case is 42 mm with fat lugs, no amount of dial printing will save it.

What the reference actually is

IWC builds the Portugieser Chronograph around a 41 mm stainless steel case, a sapphire crystal front and back, and the in-house calibre 69355, an automatic column-wheel chronograph with roughly 46 hours of reserve. Water resistance is rated at 3 bar, which is honest for a dress chronograph and a spec replica sellers often inflate. The four digits after IW are the model family; the last two are the variant code, so 371698 points to one specific dial, hand and strap combination inside that family. Confirm the dial color and strap type for that variant before you compare anything else, because the same case ships with several dial options.

Why this reference gets copied so much

The Portugieser has a clean face: two subdials, applied Arabic numerals, leaf hands and a railway-track minute ring. That layout is friendly to replica makers because there is no date window to align and no busy bezel to machine. It is unforgiving in the other direction too, since a plain dial makes every printing error visible. A crooked numeral or a subdial ring that sits a hair off center is obvious on a watch this simple.

What I check on a replica IW371698

Case and lugs

Look at the lug shape first. Genuine lugs curve down and taper, and the case band is thin enough that the watch sits flat on a 6.5 inch wrist. Replicas often thicken the mid-case to fit a bigger movement, which pushes the watch up off the wrist. Ask for a side profile photo, not just a front shot, and ask for the measured thickness.

Dial and subdials

• The 12 o'clock counter should be a 30-minute totalizer with crisp quarter marks.
• The 6 o'clock subdial is running seconds, and it should sit on the same vertical line as the counter above it.
• Numerals should be applied metal, not printed, with clean edges and no glue haze.
• The minute track should stay sharp at macro distance, not blur into a dotted line.

Pushers, crown and movement

Press both pushers. A decent chronograph snaps at start and stop and returns with a firm reset. Mushy pushers, or a start button that needs two presses, usually means a cheap quartz or a worn Asian 7750. Ask what powers it. Automatic A7750 based movements are the common pick; a Seagull ST19 is manual wind, so if the caseback is a display back and there is no rotor, that is why.

Strap, buckle and finish

Brushed surfaces should be brushed and polished surfaces polished, with a crisp line between them. Check the clasp engraving and the stitching on the leather. Crooked stitching is the fastest giveaway at arm's length.

Red flags in listings

• Only stock photos, no real images of the actual watch.
• A date window at 3 o'clock, which does not belong on this layout.
• Swiss made claims on a very low price.
• No mention of movement type or case thickness.
• Subdials that look printed flat instead of recessed.

One honest note

A replica is not the genuine watch. It will not hold value, IWC will not service it, and parts availability depends on whoever built it. Buy it as a look, not as an investment, and keep the price in line with that.