The best replica IW371787 for most buyers is a steel automatic chronograph in the 41 mm class with a two register dial, a movement whose layout matches the original layout, and a case thin enough to slide under a shirt cuff. Three criteria decide the outcome: case proportions, dial printing, and the movement inside. Reference accuracy matters more than any single feature, because a copy that gets the silhouette right passes a glance, while one that nails the dial and misses the case never does.
What the IW371787 reference is
IW371787 is an IWC reference number, and the numeric suffix is not decoration. Case metal, dial finish, and strap change between catalog entries that share a base number, so two watches from the same family can look quite different. Start by pulling the exact reference from IWC's own catalog and writing down four facts: case diameter and thickness, dial color with subdial position, hand finish, and the strap or bracelet it shipped on.
The watch it names is a two register chronograph with a slim bezel, a wide dial opening, and lugs that taper instead of blocking out. That silhouette is the hard part to copy, because it depends on case height and lug curve rather than diameter alone. Copy sellers reuse photography across references, so a listing that shows three dial variants under one number has already told you how much care went into the build.
Criterion 1: Case proportions and finishing
Measure the diameter, then check the thickness. A case that is a millimeter too tall wears like a different watch and sits badly under a cuff. Look at how the lugs bend toward the wrist, whether the bezel stays slim, and whether the brushing on the flanks runs in one direction.
Strengths of a well cut case:
- Correct diameter and height, so the watch balances on the wrist
- Lug curve that follows the wrist instead of hovering above it
- Consistent brushing and polishing, with no soft or rounded edges
Weaknesses of a cheap case:
- Oversized or slab sided, which reads wrong from across a table
- Polished surfaces that look mirror bright instead of soft
- Crystal that sits proud of the bezel or shows heavy reflections
Buy this tier if you wear the watch daily and care how it sits under a sleeve. Skip it if you only want a display piece for a drawer.
Criterion 2: Dial, hands, and printing
Dial work is where most copies fail, and it fails in small ways. Check the subdial spacing against the original, the weight of the hour markers, and whether the date window sits where it should. Printing should be crisp at the edges, not fuzzy or uneven in thickness.
Strengths of a strong dial:
- Subdials positioned to match the original layout
- Applied markers with clean edges and even lume fill
- Hands with the right shape, length, and finish
Weaknesses to watch for:
- Subdials shifted a fraction, which the eye catches before the mind does
- Text that is too large, too bold, or spaced unevenly
- Flat hands with no bevel and paint instead of polished steel
Choose a better dial if the watch will be seen up close in meetings or at dinner. A weaker dial is tolerable if the watch mostly lives under a cuff.
Criterion 3: Movement options
The movement decides how the subdials behave and how the watch feels when you wind it. Automatic chronograph copies usually run on a 7750 family base or a Sellita equivalent, both of which are proven designs with widely available parts. Quartz versions are cheaper and thinner but the seconds hand ticks instead of sweeping.
Strengths of an automatic chronograph base:
- Sweeping seconds and a chronograph that engages with real resistance
- Serviceable by any competent watchmaker
- Correct subdial layout when the base is chosen for that purpose
Weaknesses:
- Thicker than the original, which pushes the case height up
- Rotor noise on lower grade examples
- Quartz alternatives save money but lose the mechanical feel entirely
Pick an automatic if you want the watch to behave like the real thing. Pick quartz only if thickness and budget matter more than sound and feel.
Criterion 4: Strap, clasp, and hardware
Hardware is cheap to upgrade and cheap to ruin. Leather should have a tight grain and stiff edges rather than a plastic sheen. If it is a deployant or folding clasp, check that it closes with a firm click and does not snag.
- Good: stitched edges, signed buckle, spring bars that hold firmly
- Poor: thin leather, loose stitching, clasps that rattle when you move
Pre-purchase checklist
- Confirm the reference number and its exact specification from the official catalog
- Ask for photos taken in daylight, straight on, with no filters
- Request a case back and movement photo, plus a video of the chronograph running
- Ask for measured diameter and thickness with calipers
- Confirm the water resistance claim in writing, and do not swim with it regardless
- Check the return window and who pays return shipping
Legal and practical notes
Counterfeit watches are illegal to import and sell in many countries, including the United States, and customs seizures happen. A replica is not an investment, it has no resale market, and no maker warranty applies. Weather sealing, shock protection, and long term parts availability are all unknown. Treat any purchase as a disposable cost, not a collection piece, and keep the transaction terms in writing.
Which build fits which buyer
For everyday wear, take the automatic with the best case and dial you can find, and accept the extra thickness. For occasional wear, a mid tier automatic with a decent dial is enough, and you can upgrade the strap yourself. For a display only piece or a gift gag, quartz is the honest choice, because it removes the pretense of mechanical behavior without pretending otherwise.