Quick answer
A replica Portofino Automatic 37 is worth buying only if it matches three numbers: a 37 mm case diameter, roughly 9.4 mm case thickness, and a 28,800 vph automatic movement with the date at 3 o'clock. Get those right and the watch wears like the genuine article on a smaller wrist. Miss them and no amount of polishing hides the gap. The checklist below walks through each measurement and detail in the order that exposes problems fastest.
Prerequisites
- Digital calipers or a micrometer that reads to 0.01 mm
- A 10x jeweler's loupe
- A timing app or a timegrapher for rate and beat error
- The exact reference you intend to match (for example IW458601 or IW458602)
- A spring bar tool and a microfiber cloth
- Manufacturer photos of that reference on screen for side-by-side comparison
Pin down the reference first. The Portofino Automatic 37 family spans several dial colors, strap options, and two movement generations: an older caliber 35111 derived from the Sellita SW300 with about 42 hours of reserve, and a newer in-house caliber 32111 with a much longer reserve. Replica sellers mix these up constantly, so decide which one you are checking before you start.
How to inspect the watch, step by step
- Measure the case across the dial at the 9 and 3 o'clock positions without the crown. A correct build lands at 37.0 mm, and anything from 36.7 to 37.3 mm is acceptable.
- Measure the case thickness from the caseback to the top of the crystal. The target is about 9.4 mm; a reading over 10 mm means a thick movement spacer or a domed crystal that is too tall.
- Measure the lug width with the strap removed. Expect roughly 18 mm at the lugs, and check that the strap tapers toward the buckle rather than staying straight.
- Examine the dial under the loupe. The indices should be applied metal, faceted, and set level; printed indices on a Portofino Automatic 37 are an instant downgrade.
- Check the date window at 3 o'clock. The aperture must sit on the same horizontal line as the center of the crown, with crisp edges and no white border ring.
- Inspect the hands. They should be leaf shaped, polished on the bevels, and long enough that the minute hand reaches the printed track without overshooting it.
- Look at the crystal at an angle under a light. Sapphire with an anti-reflective coating shows a faint blue or purple tint, while cheap mineral glass shows none and scratches on contact with a key.
- Listen to the movement. A 28,800 vph caliber produces a fast, fine sweep on the seconds hand, not a visible tick, and the rotor should spin with a light whir rather than a rattle.
- Time the watch on a full wind for 24 hours. A well-built replica holds within plus or minus 10 seconds per day; a rate beyond 20 seconds per day signals a poorly regulated or low-grade movement.
- Wind and set the crown. It should turn smoothly, click into each position cleanly, and have no side-to-side wobble when pushed in.
- Remove the strap and check the leather. Alligator grain should follow the curve of the case, and the buckle should carry the correct engraving depth and font.
- Compare your photos against the reference images at 100 percent zoom, checking the logo thickness, the text spacing, and the position of the model line above the date.
Red flags that justify a return
- A case that measures 38 mm or more
- A date window placed at 4:30 or off the crown line
- Printed instead of applied indices
- A 21,600 vph movement with a slow, choppy sweep
- Mineral glass that shows no anti-reflective tint
- A caseback engraving with blurred lettering or the wrong reference number
- A stated water resistance of 50 m with no gasket visible at the caseback threads
What even a good replica cannot match
Water resistance on any replica is a claim, not a guarantee. The genuine watch is rated to 5 bar under ISO 22810, and that rating depends on tested gaskets and a pressure-tested case. Do not swim or shower with a replica, however confident the seller sounds. Movement finishing is the second gap: a genuine caliber shows Geneva stripes, blued screws, and hand beveling that a machine-finished clone does not reproduce. Third, precious-metal versions use solid red gold, and a plated case will wear through at the crown and lugs within a few years of daily use.
Care after purchase
Keep the watch away from steam and hot water, wipe the case with a dry cloth after handling, and have the movement regulated every two to three years if it drifts. Store it on a soft pad with the strap relaxed so the leather keeps its curve. If you rotate several watches, wind this one weekly to keep the lubricants moving.
Counterfeit sales carry real legal exposure in the United States, since selling goods that copy a trademarked design is infringement, and buyers should treat any seller claim of factory-original parts as marketing rather than fact.