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Scan for outdated or missing drivers - takes under a minuteDriver Scan →Repair Windows errors before they cause bigger problemsFix Now →The “record-thin” Bulgari Octo Finissimo Automatic is specifically the 2017 titanium model: its 40 mm case measured 5.15 mm thick around the 2.23 mm BVL 138 automatic movement. That historic configuration is not the same as the currently listed steel and yellow-gold 40 mm versions, whose cases measure 6.40 mm. Hodinkee’s 2017 reviewer described the titanium watch as remarkably light and comfortable; current specifications and prices below are tied to the exact Bulgari references and regional pages.
Which Octo Finissimo Automatic is the record-thin watch?
The record claim belongs to the 2017 sandblasted titanium Octo Finissimo Automatique, reference not stated in the cited launch coverage. Hodinkee reported a 40 mm case only 5.15 mm thick, housing Bulgari’s 2.23 mm BVL 138 automatic movement. Those figures describe that launch-era titanium configuration, not every watch now sold under the Octo Finissimo name. Hodinkee’s March 22, 2017 launch report gives the original measurements.
Bulgari’s current product pages instead list two 40 mm examples with 6.40 mm cases: steel reference 103431 and yellow-gold reference 103812. The brand does not label these current models as 5.15 mm-thick watches. They share the BVL 138 movement, 60-hour power reserve, and 100 m water-resistance rating, but differ in case material, dial, regional listing, and displayed price.
| Version | Case and dial | Case size | Movement and reserve | Water resistance | Displayed price |
|---|---|---|---|---|---|
| 2017 titanium Automatique; reference not stated in Hodinkee launch report | Sandblasted titanium; dial and bracelet details are not specified in the cited launch measurements | 40 mm diameter; 5.15 mm thick, per Hodinkee’s 2017 report | BVL 138; 2.23 mm thick, per Hodinkee’s 2017 report | 30 m, per Hodinkee’s 2017 report | Not stated in the cited launch report |
| Current steel, ref. 103431 | Steel; silver-colored dial, as identified on Bulgari’s international product page | 40 mm diameter; 6.40 mm thick, per Bulgari’s page accessed October 8, 2026 | BVL 138 automatic; 60 hours, per Bulgari’s page accessed October 8, 2026 | 100 m, per Bulgari’s page accessed October 8, 2026 | €15,000 including taxes, on Bulgari’s international page accessed October 8, 2026 |
| Current yellow gold, ref. 103812 | Yellow gold; blue dial, as identified on Bulgari’s Hong Kong product page | 40 mm diameter; 6.40 mm thick, per Bulgari’s page accessed October 8, 2026 | BVL 138 automatic; 60 hours, per Bulgari’s page accessed October 8, 2026 | 100 m, per Bulgari’s page accessed October 8, 2026 | HK$380,000, on Bulgari’s Hong Kong page accessed October 8, 2026 |
Current product specifications and localized prices: Bulgari steel reference 103431 and Bulgari yellow-gold reference 103812. The two displayed prices are snapshots from different markets and apply to different references; they are not a like-for-like price comparison.
#1 Best Overall
- With bold design and superior accuracy, Citizen Atomic Timekeeping watches synchronize to an atomic clock with a margin of error of just one second in 100,000 years.
- An Eco-Friendly Evolution: Citizen launches first Titanium Watch in 1970. More than 50-year-old evolution of innovative timepieces crafted from proprietary space-age material.
- Benefits of Super Titanium: Lightweight for Better Comfort, Scratch Resistant, Gentle on Skin, and Rust Resistant. Five times harder and 40% lighter than stainless steel.
- 1/5 Second Chronograph Measures up to 60 Minutes, 12/24 Hour Time, Date, Anti-Reflective Sapphire Crystal
- Sustainably powered by any light, with our Eco-Drive technology this watch never needs a battery. 200 Meter Water Resistant and 5 Year Limited Warranty
What makes the watch so thin?
A movement built around a micro-rotor
The BVL 138 winds itself through a platinum micro-rotor rather than a full-size rotor sitting over much of the movement. That layout allows automatic winding in a notably thin movement. Bulgari’s current listing for gold ref. 103812 describes a 2.23 mm-thick movement with hand decoration, 31 jewels, a frequency of 21,600 vibrations per hour (3 Hz), and a 60-hour power reserve. Bulgari’s current gold-model specifications provide those movement details.
Movement thickness is not case thickness
The 2.23 mm figure measures the movement, not the complete watch. The 2017 titanium watch was reported at 5.15 mm overall, while the current steel and gold pages each give a 6.40 mm case thickness. The gap between those numbers is not a simple measure of a bezel or caseback: the movement and the assembled watch are different measurements, and the cited pages do not provide a component-by-component breakdown.
Rank #2
- Sleek & Functional Design: This sophisticated titanium men's watch showcases a distinctive dial layout with dedicated markers for minutes, 12-hour, and 24-hour time displays. Arabic numerals ensure optimal legibility, while the bold red-tipped second hand injects a subtle yet striking accent. The inclusion of a practical date window further elevates its everyday versatility.
- Lightweight & Durable Titanium Construction: Crafted from premium titanium, the case combines brushed and polished finishes for a refined yet rugged aesthetic. Renowned for its featherlight weight and exceptional resilience, titanium offers superior corrosion resistance. The screw-down case back enhances durability.
- Clear AR Coated Sapphire Lens & Super Luminous: Fitted with an anti-reflective sapphire crystal, this automatic watch delivers unmatched clarity and scratch resistance. The watch hands and markersare coated with super-luminous material for easy readability even in low-light conditions.
- Precision Japanese Movement & 10ATM Water-Resistant: Powered by a precise Miyota 8215 automatic movement, this timepiece ensures accurate timekeeping and long-term reliability. With a 10ATM water resistance rating, it’s built to accompany you on outdoor adventures without compromise.
- Quick-Release Nylon Strap for Comfort: The lightweight nylon strap prioritizes comfort for all-day wear, while the quick-release mechanism allows for effortless strap changes to suit any occasion. Low-maintenance and durable, it’s designed for convenience.
What does the hands-on review say about wearing it?
In Hodinkee’s 2017 “A Week On The Wrist” account, the reviewer found the titanium watch remarkably light and comfortable at 40 mm by 5.15 mm. The review also says the matching titanium bracelet was where the watch came into its own. Those are that reviewer’s impressions of the launch-era titanium model, not a claim based on testing the current steel or gold references. Read the 2017 extended-wear review.
Ultra-thin construction brings a practical service consideration. The same review discusses tight clearances in ultra-thin watches and the possibility that work may require a specialist watchmaker. It is a general caution about the category, not evidence of a specific failure rate or a durability verdict for these references. Ask an authorized service provider about the requirements for the exact watch being considered.
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Rank #3
- Sleek & Functional Design: This sophisticated titanium men's watch showcases a distinctive dial layout with dedicated markers for minutes, 12-hour, and 24-hour time displays. Arabic numerals ensure optimal legibility, while the bold red-tipped second hand injects a subtle yet striking accent. The inclusion of a practical date window further elevates its everyday versatility.
- Lightweight & Durable Titanium Construction: Crafted from premium titanium, the case combines brushed and polished finishes for a refined yet rugged aesthetic. Renowned for its featherlight weight and exceptional resilience, titanium offers superior corrosion resistance. The screw-down case back enhances durability.
- Clear AR Coated Sapphire Lens & Super Luminous: Fitted with an anti-reflective sapphire crystal, this automatic watch delivers unmatched clarity and scratch resistance. The watch hands and markersare coated with super-luminous material for easy readability even in low-light conditions.
- Precision Japanese Movement & 10ATM Water-Resistant: Powered by a precise Miyota 8215 automatic movement, this timepiece ensures accurate timekeeping and long-term reliability. With a 10ATM water resistance rating, it’s built to accompany you on outdoor adventures without compromise.
- Quick-Release Nylon Strap for Comfort: The lightweight nylon strap prioritizes comfort for all-day wear, while the quick-release mechanism allows for effortless strap changes to suit any occasion. Low-maintenance and durable, it’s designed for convenience.
How should you interpret water resistance and current listings?
Do not assign the family one water-resistance figure. Hodinkee reported 30 m for the 2017 titanium Automatique; Bulgari lists 100 m for current steel ref. 103431 and yellow-gold ref. 103812. These are different configurations and sources, so the higher current rating does not retroactively apply to the titanium original. For a particular watch, use the rating and care guidance for its exact reference.
The Bulgari product pages accessed October 8, 2026, displayed €15,000 including taxes for steel ref. 103431 on the international site and HK$380,000 for yellow-gold ref. 103812 on the Hong Kong site. Prices, tax treatment, availability, and local terms can change; confirm them with Bulgari in the market where you intend to buy.
Rank #4
- Swiss Made Watch
- Movement: Automatic MIDO caliber with Day/Date calendar - Power reserve 80 hours
- Case Type: Diver-style Titanium case with black rotating bezel - Capable of withstanding pressures of up to 20 bar (200 m/660 ft), and equipped with a screw-down crown, this watch offers optimal protection against water.
- Case Size: 42.5mm - Case Thickness: 11.8mm - Anthracite color dial offering indexes filled with Super-Luminova and skeletonised hands - Crystal: Sapphire crystal with double sided anti-reflection treatment
- Band Type: Titanium bracelet - Folding clasp with diving extension - Band Width: 22mm
Where does the 40 mm BVL 138 watch sit in the collection?
Bulgari dates the Octo Finissimo collection’s debut to 2014. Its 2026 collection story also presents a distinct 37 mm interpretation using the BVF 100 movement, listed there as 2.35 mm thick and 31 mm across. That smaller collection variant should not be confused with the 40 mm BVL 138 watches discussed here. Bulgari’s Watches & Wonders Geneva 2026 collection story provides that separate context.
At launch, Bulgari CEO Jean-Christophe Babin described the brand’s ambition this way: “We are used at Bulgari to go where others don’t. This is part of our soul and spirit.” Hodinkee attributed that remark to Babin in its 2017 launch report; it is launch-era context, not a current statement.
Quick Recap
Best Value
- Swiss Made Titanium Watch for Men and Women
- Movement: Automatic Mido Caliber - Power reserve 80 hours
- Case Type: Titanium TV-shaped case with see-through case back and screw-down crown with crown guards
- Case Size: 40mm - Case Thickness: 11.48mm - Crystal: Sapphire crystal with double sided anti-reflection treatment
- Strap: Titanium Bracelet with Folding Clasp Closure - Lug Width: 22mm
What to verify before choosing a reference
- Reference and year: distinguish the 2017 titanium watch from current listings such as steel 103431 and yellow gold 103812.
- Case: check the stated thickness as well as diameter; the reported titanium original and listed current models differ.
- Material and dial: confirm the precise case and dial configuration rather than relying on the collection name alone.
- Movement and functions: current steel and gold listings identify BVL 138 automatic winding, with hours, minutes, and small seconds; the current gold page supplies additional movement specifications.
- Water resistance: use the rating for the exact reference, not another Octo Finissimo configuration.
- Local price and stock: confirm current terms in your market because the cited displayed prices are regional snapshots for different references.
- Service: ask about suitable servicing for an ultra-thin automatic before purchase or maintenance.
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.
