ZF Factory IWC Portofino Chronograph IW391023 “Portofino Chrono Blue” Stainless Steel Super Clone Replica

Correct Model Identification (Confirmed)

The watch shown is the IWC Portofino Chronograph, reference IW391023, the stainless-steel blue-dial variant.

This identification is confirmed by the following fixed characteristics:

• 42mm Portofino chronograph case in stainless steel

• Deep blue sunburst dial

• Tri-compax chronograph layout

  • 30-minute counter at 12

  • Small seconds at 9

  • 12-hour counter at 6

• Day + date window at 3 o’clock

• Roman numerals at 12 and 6 only

• Slim baton hour markers

• Leaf-shaped hour and chronograph hands

• Pump-style chronograph pushers

• Solid caseback

Within the Portofino family, IW391023 is widely regarded as the most versatile chronograph reference, balancing color, formality, and daily wearability.

Why This ZF Version Qualifies as a Super Clone

Chronograph replicas usually fail after the honeymoon period. The first tells appear in reset alignment, pusher feel, or dial tension once the watch is worn regularly. ZF avoids those failures by building the watch around a proper chronograph movement, not forcing the case to hide its limitations.

All chronograph functions are fully functional:

• Central chronograph seconds

• 30-minute chronograph counter

• 12-hour chronograph counter

• Running seconds

• Fully working day and date display

Nothing is decorative. Everything exists to be used, which is the only way a chronograph makes sense long term.

Case Proportions and Stainless Steel Finish

At 42mm, the case matches the genuine Portofino Chronograph dimensions. While any 7750-based chronograph carries inherent thickness, ZF manages the mid-case profile well enough to keep the watch wearable under a cuff in real conditions.

The polished stainless steel case is evenly finished, avoiding overly aggressive mirror polishing. Reflections remain controlled indoors, which is especially important with a blue dial that can otherwise feel flashy.

Lug curvature and pusher placement preserve the Portofino’s refined silhouette rather than drifting toward sport-chrono territory.

Blue Dial Execution and Chronograph Balance

The blue dial is restrained rather than saturated. Under indoor lighting it appears deep navy; under direct light it reveals a controlled sunburst without glare.

Key strengths of the dial execution:

• Correct sub-dial spacing with no crowding

• Blue dial and steel hands maintain contrast without harshness

• Day/date window integrates cleanly without cutting into the dial rhythm

• Roman numerals anchor the dial without overpowering it

The minute track is evenly printed and visually secondary, allowing the eye to read time first and chronograph information only when needed.

Crystal and Optical Behavior

The watch uses a sapphire crystal with anti-reflective coating, keeping glare under control without introducing blue or purple haze. This is critical on blue dials, where poor AR treatment becomes obvious in office lighting.

The crystal profile remains flat and restrained, preserving the classic Portofino appearance.

Movement: Dandong 7750 Modified to Cal. 4601 Architecture

ZF equips this model with a Dandong 7750 automatic chronograph movement, modified to follow the IWC Cal. 4601 functional layout used in the genuine Portofino Chronograph.

Practical ownership characteristics include:

• 28,800 bph automatic operation

• Stable chronograph engagement

• Clean start, stop, and reset behavior

• Reliable day/date switching

• Predictable hand-setting resistance

This is a functional modification focused on stability and usability, not decorative mimicry. As with all mechanical chronographs, sensible use is assumed—reset only when stopped and avoid unnecessary abuse.

Strap Material and Wearing Comfort

The watch is fitted with an Italian calfskin leather strap in blue, matching the dial tone without competing with it. The strap is supple but structured, with light padding that supports the case without adding bulk.

Break-in is smooth, and the strap maintains shape over time, keeping the watch centered during extended wear.

Who This Watch Is For

This model is for wearers who want a true dress chronograph with color—something more expressive than white or silver, but still appropriate for professional and formal environments.

It is not intended for those seeking sporty chronographs or ultra-thin profiles. This watch prioritizes balance, function, and long-term coherence.

ZF Replica vs Genuine Comparison

This ZF Factory Portofino Chronograph IW391023 succeeds by keeping color, complexity, and proportion in balance, offering a blue-dial dress chronograph that remains coherent and usable over time, with the final judgment—rightly—left to the wearer.