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A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11The IWC Portofino Hand-Wound Moon Phase IW516401 is a large, manually wound dress watch built around an eight-day stated power reserve and a moon-phase display. Its silver dial, steel case and classic styling make a composed package, but the 45 mm diameter, 3 bar water-resistance rating and need for regular winding are decisive ownership considerations. It suits someone who values a visible mechanical ritual and an unusually long interval between full winds more than compact proportions or carefree water use.
What the IW516401 is—and what it is not
This review is specific to reference IW516401: a stainless-steel Portofino with a silver dial and dark-brown Santoni alligator-leather strap. It is distinct from the red-gold IW516403 and from IWC’s separate automatic Portofino moon-phase models. IWC describes the moon phase as the first integration of that display into the classic Portofino with an eight-day hand-wound movement; that is the brand’s product-history claim, not an independent historical assessment. IWC’s product page presents the model as a dress watch with a moon phase and long reserve.
The design proposition is clear: traditional Portofino styling, several useful indications and a long stated reserve, in a case that is anything but discreet in size. The watch’s appeal depends less on whether those features are impressive on paper than on whether its scale and manual-winding routine suit the way you wear a dress watch.
IW516401 specifications
| Specification | IW516401 |
|---|---|
| Case and dial | Stainless steel; silver dial |
| Strap | Dark-brown Santoni alligator leather |
| Case diameter and height | 45 mm diameter; 13.1 mm height, as listed on IWC’s current product page |
| Strap width | 22 mm |
| Movement | IWC-manufactured calibre 59800; manual winding |
| Power reserve | 192 hours (eight days), rated by IWC; the manual describes the reserve as approximate when fully wound |
| Indications | Date, small hacking seconds, power reserve and moon phase |
| Crystal and caseback | Arched-edge sapphire crystal with antireflective coating on both sides; see-through sapphire caseback |
| Water resistance | 3 bar, as published by IWC |
Specifications are from IWC’s official product page and model manual. The 13.1 mm height is the current product-page figure; older catalogue figures may differ slightly. The 22 mm measurement is the stated strap width, not a guarantee that any replacement strap will fit the case: check end shape and compatibility before buying one.
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#1 Best Overall
- This is a panoramic large aperture moon phase automatic mechanical watch designed by Swiss chief designer Etienne Ruffieux, inspired by the sun, moon, and stars. Precision‑engraved moon disc with daily lunar cycle display, fully presenting the entire cycle of nature's waxing and waning phases. The watch was honored with the Italian A' Design Award for its outstanding original design. It is an automatic large moon phase mechanical watch brimming with the romantic charm of celestial bodies.
- In-house CAL.A4610 fully automatic mechanical movement, bidirectional automatic winding system, 28,880 vibrations per hour, 27 ruby bearings. Exquisite perlage and geneva stripes finishing, edge chamfering process, white gold plating, and engraved gold-plated brand logo highlight exceptional high-end craftsmanship.
- In-house CAL.A4610 fully automatic mechanical movement. Enhanced power reserve technology delivers an extended 80-hour power reserve (twice that of standard mechanical movements). This technology enables a more even and gradual release of the mainspring, resulting in more precise and stable timekeeping.
- Before AGELOCER introduced its panoramic moon phase watch with a large aperture, traditional moon phases were displayed through small windows. This groundbreaking 28.5mm large aperture moon phase design pioneered the industry's first panoramic moon phase watch. To power the large moon phase disc and prevent the dial from shifting due to wrist movement inertia during wear, the design team spent hundreds of hours on repeated testing.
- They completely re-engineered the watch's reversing and drive mechanisms, thickened the toggle spring, and boosted the power output of the rotating disc—using sophisticated R&D to counteract inertia. This technology is now protected by a Chinese utility model patent.
What the eight-day hand-wound movement adds
Calibre 59800 is manually wound, and IWC rates it for 192 hours of power reserve. That is a stated full-wind figure, not an independently verified result here; IWC’s manual calls the reserve approximate when fully wound. The long interval means you are not winding it every morning, but the watch still depends on you to wind it and keep track of its remaining reserve.
The power-reserve display makes that status visible, which is especially useful on a watch with a multi-day reserve. Manual winding can also be part of the pleasure: it creates a direct, recurring interaction with the movement rather than the set-and-forget experience many owners expect from an automatic watch. The trade-off is practical as well as philosophical. If the watch sits unworn long enough to run down, you will need to wind and reset it as needed before wearing it again.
Rank #2
- 14K GOLD PLATED VINTAGE DRESS WATCH – Features an elegant gold tone case with a clean dial and bold Arabic numerals, designed for men who appreciate classic vintage style. Suitable as an everyday wear watch or for formal occasions, this analog watch effortlessly elevates any outfit.
- SUN MOON PHASE DISPLAY – The decorative sun-moon phase dial adds a sophisticated vintage complication that sets this timepiece apart from ordinary mens dress watches. A stunning conversation piece and a standout feature among gold tone analog watches for men.
- ACCURATE JAPANESE QUARTZ MOVEMENT – Powered by a precise Japanese quartz movement for reliable everyday timekeeping with minimal maintenance. Built to last and backed by the Peugeot reputation for quality affordable luxury watches for men.
- GENUINE LEATHER STRAP – Soft, durable, and fully adjustable genuine leather band fits a range of wrist sizes comfortably. Perfect as a mens leather watch for the office, date nights, weddings, or any special occasion.
- PEUGEOT LIFETIME WARRANTY & GIFT READY – Every Peugeot watch is backed by a Lifetime Warranty including free battery replacement for the life of the watch. Arrives beautifully gift boxed — ideal as a birthday gift, anniversary gift, graduation gift, or holiday gift for men.
Moon phase: useful display, with accuracy limits not stated
The moon-phase display is the watch’s defining complication alongside its extended reserve. IWC’s Australian product page explains that a lunation lasts 29 days, 12 hours, 44 minutes and 2.88 seconds, so reduction gearing is used to approximate the lunar cycle. That is IWC’s general explanation of the mechanism, not an accuracy interval established specifically for IW516401. The reviewed official materials do not state this reference’s moon-phase error rate.
In everyday use, the moon phase is primarily a visual complication: it adds depth and character to the dial, while the date and small hacking seconds provide more direct day-to-day utility. Buyers who want a moon display should value the presentation and the mechanical interest rather than assume a precision figure that IWC does not publish for this reference.
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- This is a precision panoramic large aperture moon phase automatic mechanical watch crafted from blue aventurine, the material that most closely resembles the starry night sky, designed by Swiss chief designer Etienne Ruffieux, inspired by the sun, moon, and stars. The intricately carved luminous moon changes once daily, fully showcasing the entire cycle of nature's waxing and waning phases. This watch has been awarded the European Design Award for its outstanding original design.
- In-house CAL.A4610 fully automatic mechanical movement, bidirectional automatic winding system, 28,880 vibrations per hour, 27 ruby bearings. Exquisite perlage and geneva stripes finishing, edge chamfering process, white gold plating, and engraved gold-plated brand logo. Delivers an extended 80-hour power reserve (twice that of standard mechanical movements). This technology enables a more even and gradual release of the mainspring, resulting in more precise and stable timekeeping.
- The moon phase disc in Agelocer's in-house CAL.A4610 automatic mechanical movement features a precision 31-tooth structure. It advances one segment every 22.846 hours, completing a full cycle every 29.51 days to achieve a 708.23-hour lunar cycle. (Conventional moon phase discs use a 59-tooth gear, advancing one notch every 24 hours to complete a full cycle in 29.5 days, resulting in a 708-hour lunar cycle.)
- The astronomical lunar cycle is 29.53 days (708.72 hours), meaning conventional moon phases accumulate a one-day error every 2.7 years. The Agelocer moon phase watch accumulates one day of error every 4.1 years, offering greater precision than traditional 59-tooth moon phase mechanisms.
- The dial is made of natural blue aventurine from Brazil. Its deep blue or violet-blue color from scaly vivianite contained within quartz crystals during geological formation. It shimmers with a beautiful, soft glow, like sky full of stars, make it most star-like natural dial material available today. In this panoramic large moon phase watch, as the dynamic moon perfectly glides across the starry surface of the blue aventurine dial, it feels as if the cosmic starry sky is right before your eyes.
Fit, wearability and water resistance
45 mm is the main fit decision
At 45 mm across and 13.1 mm high, IW516401 is a substantial dress watch. Its formal styling does not make it a small or low-profile option. The diameter may dominate a narrow wrist or sit awkwardly under a close-fitting shirt cuff, so trying it on is more useful than judging it from photographs. Case shape and wrist proportions affect the impression, but the published dimensions alone make clear that this is not a compact Portofino.
3 bar is a modest rating
IWC lists water resistance at 3 bar. Report that as the watch’s published rating; it is not a basis for treating the watch as a swimming or diving choice. The official materials cited here do not provide a detailed activity guide for this particular reference, so owners should follow IWC’s current care advice rather than infer a use recommendation from the number alone.
Rank #4
- Luxurious Genuine Leather：Crafted from top - grade genuine leather, this strap exudes luxury. The natural texture offers a rich and sophisticated look.
- Soft & Comfortable：The leather is soft to the touch, conforming to the wrist for a comfortable fit. It provides a pleasant wearing experience throughout the day.
- Classic Design：With a timeless design, it complements various watch styles. Whether a classic or modern watch, it adds an elegant touch.
- Customizable Fit：Equipped with multiple holes, it can be easily adjusted to fit different wrist sizes, ensuring a perfect and secure fit.
- Please measure the width of your watch lug before ordering. It is important that your watch's lug width is the exact width of the band you select.
Price and availability depend on the market
Price and stock status vary by region and can change. A Swiss IWC listing surfaced at CHF 12,300 including taxes, while IWC’s Australian listing described the model as having limited availability and directed customers to contact IWC. These are separate regional listings, not a global price or a guarantee of current stock. Check the relevant local IWC page or contact an IWC boutique for an up-to-date quote and availability. Swiss listing; Australian listing.
Who should consider the IW516401?
- Consider it if you want a traditional steel Portofino with a moon phase, appreciate manual winding and prefer a long stated reserve between full winds.
- Try it on before deciding if you favor restrained dress-watch proportions; 45 mm is prominent, and its 13.1 mm height may matter under a cuff.
- Look elsewhere if you want an automatic movement, minimal owner interaction, a smaller case or a watch for regular water activities.
For a comparison with another moon-phase dress watch, evaluate case diameter and thickness, winding system, stated reserve, dial indications and legibility, water-resistance rating, materials and local price. A meaningful head-to-head requires current, independently sourced specifications for the alternative; the IW516401’s specifications alone do not establish how it compares with any particular competitor.
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Quick Recap
Best Value
- Luxurious Genuine Leather：Crafted from top - grade genuine leather, this strap exudes luxury. The natural texture offers a rich and sophisticated look.
- Soft & Comfortable：The leather is soft to the touch, conforming to the wrist for a comfortable fit. It provides a pleasant wearing experience throughout the day.
- Classic Design：With a timeless design, it complements various watch styles. Whether a classic or modern watch, it adds an elegant touch.
- Customizable Fit：Equipped with multiple holes, it can be easily adjusted to fit different wrist sizes, ensuring a perfect and secure fit.
- Please measure the width of your watch lug before ordering. It is important that your watch's lug width is the exact width of the band you select.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
