The steel Patek Philippe Cubitus 5821/1A-001 wears broad and conspicuous, but its headline 45 mm measurement is the diagonal across its rounded-square case—not its straight width. Patek lists an 8.3 mm thickness; a 2024 Monochrome review measured 44.5 mm across including the crown and 44.9 mm lug-to-lug, and described the watch as comfortable on the pictured 17.5 cm and 18 cm wrists. Those observations suggest a slim profile with substantial visual presence, not a universal fit guarantee.
What does 45 mm mean on the Cubitus?
Patek Philippe specifies the Cubitus 5821/1A-001 at 45 mm, measured diagonally from 10 to 4 o’clock. That is not a conventional straight side-to-side width, so comparing “45 mm” directly with the diameter of a round watch can exaggerate the apparent size difference. The rounded-square outline still spreads across the wrist: the diagonal captures its corners, while width and lug-to-lug measurements help describe its footprint more directly.
In its 30 October 2024 review, Monochrome reported 44.5 mm width including the crown, 44.9 mm lug-to-lug, and 8.3 mm thickness. Patek’s official product page also gives 8.3 mm thickness. Together, these measurements describe a wide-looking case that is notably thin for its footprint; they do not, by themselves, determine whether it will suit a particular wrist.
How does it feel and look on the wrist?
Monochrome’s Brice Goulard reported that the team handled the collection for several hours. The review describes pronounced wrist presence alongside comfortable wear, noting that the bracelet rolls around the wrist. Its pictured reviewers had wrists of about 17.5 cm and 18 cm. These are specific observations from that review, not a fit test across wrist shapes or a guarantee for every wearer.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
- VERIFY YOUR WATCH MODEL & MEASURE THE CORRECT SIZE USING A RULER – Watch Parts Are Model and Size Specific. Please Verify Compatibility Before Purchasing.
- Check Compatibility: This aftermarket replacement link measures 17mm wide and 6mm long (0.25 inch). Designed for the 41mm Patek Philippe Nautilus models, please measure your existing link to ensure proper fit before purchasing.
- Quality Construction: Crafted from high-quality 316L stainless steel, this heavy-duty link features a matte finish on the sides and edges, providing a durable and stylish upgrade for your Patek Philippe Nautilus watch band.
- Perfect Fit for Multiple Models: This link is compatible with Patek Philippe Nautilus models 5711, 5726, 5811, 5990, 5980, and more. Verify your model number for compatibility to ensure an exact fit with your watch.
- Easy Installation: Each link comes with 2 pins and 2 tubes for straightforward installation. Enjoy a seamless replacement experience that enhances the appearance and functionality of your watch band.
The square case occupies visual space differently from a round watch: its corners make the watch read as broad, even though the case is only 8.3 mm thick. Bracelet articulation may help it follow the wrist, but wrist circumference alone cannot settle the fit. Wrist shape, how close the case sits to the wrist edges, and personal preference for a prominent watch all matter.
The steel bracelet integrates into the case and alternates polished surfaces with vertical satin brushing. Its shape and finishing reinforce the case’s broad, architectural look. The olive-green dial has horizontal embossing and a sunburst finish; white-gold applied markers and hands carry white luminescent coating, according to Patek Philippe.
How does the Cubitus compare with the Nautilus 5711 and 5811?
Monochrome’s October 2024 review published measurements for the steel Cubitus and two Nautilus models. The figures below follow the same order in each row: diagonal, width including crown, lug-to-lug, and thickness. They are the review’s measurements, not Patek Philippe’s official dimensions for every model.
Rank #2
- Special note: This 21mm watch band is only suitable for Patek Philippe AQUANAUT 5167A 5167R 5164G 5164R. Not suitable for other brands
- PERFECT CASE CONNECTION：The unique design utilizes an ABS plastic insert to seamlessly connect to the case. The curved end ensures a perfectly tight fit to the watch with zero jarring.Seamlessly hugging the case and lugs.
- EXCEPTIONAL MATERIALS AND DURABILITY : Our curved end leather straps are made out of the Premium full grain leather.The backside of the strap has an extra layer of soft leather for added comfort and durability.
- Short size band 80mm, long size band 127mm. Suitable for wrist circumference 149mm-221mm
- Reusable inner and outer packaging (not disposable) includes:watch strap + removal tools + spring bars+packing case
| Model | Diagonal | Width including crown | Lug-to-lug | Thickness |
|---|---|---|---|---|
| Cubitus 5821/1A-001 | 45 mm | 44.5 mm | 44.9 mm | 8.3 mm |
| Nautilus 5711A | 40 mm | 44.1 mm | 44.5 mm | 8.3 mm |
| Nautilus 5811G | 41 mm | 44.5 mm | 45 mm | 8.2 mm |
The Cubitus’s diagonal figure is larger because it is measured across the square case; its reported width and lug-to-lug figures are close to those of the Nautilus examples. That helps explain why the 45 mm headline does not tell the whole fit story. Similar measurements do not make the watches feel identical: the Cubitus’s rounded-square outline and embossed green dial create a different visual effect from the Nautilus designs.
The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →What movement and everyday specifications does it have?
The 5821/1A-001 uses Patek Philippe’s self-winding 26-330 S C caliber. Manufacturer specifications list a date at 3 o’clock, central seconds, stop-seconds, a 21K gold central rotor, 35–45 hours of power reserve, and a frequency of 28,800 semi-oscillations per hour (4 Hz). Patek’s October 2024 launch technical data lists 212 parts and 30 jewels. These are published specifications, not independent performance-test results.
Patek specifies 30 m water resistance, a screw-down crown, and a sapphire crystal caseback. The water-resistance figure is the documented rating; it is not a blanket statement of suitability for swimming or diving.
Rank #3
- 100%brand new and quality,easy to adjust the length to fit the wrist,one size fits everyone.
- Made Italian cowhide material ,environmentally friendly and healthy,Softness is moderate, wear very comfortable.
- Softness is moderate, wear very comfortable,Compression molding, sturdy and durable,Wearable strap/wrist strap,suitable for original watch.
- Easy to insert and remove,very suitable for your watch.
- Exquisite craftsmanship and stylish design are perfect gifts for friends and family.
What is the steel Cubitus price?
Patek Philippe’s official product page displayed a price of £36,740 for the United Kingdom when accessed on 4 October 2026. It is a regional displayed price, not a universal price or confirmation of availability. Monochrome reported CHF 35,000, EUR 40,900, and USD 41,243 including taxes in its 30 October 2024 review; those are historical figures and should not be read as current prices.
Neither those published prices nor the product page establish current boutique stock, allocation, or pre-owned market value.
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsWhat is the Cubitus design meant to convey?
Patek Philippe introduced the Cubitus collection in 2024 in three launch versions; the steel 5821/1A-001 was the olive-dial model. The company frames the collection as a new interpretation of “elegant sporty” style, with a rounded-corner square shape blending square, circle, and octagon. That is the maker’s design description rather than an independent assessment.
On Patek Philippe’s collection page, President Thierry Stern described his intention: “I would like this watch to have a real sporty, fresh spirit. Capturing the essence of a convertible car.” The 5821/1A-001 expresses that approach through a broad, low steel case, integrated bracelet, and vivid horizontal dial texture.
Quick Recap
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.
