The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →The Longines Ultra-Chron Carbon, reference L2.839.4.52.2, pairs a 43 mm titanium-and-carbon case with a 5 Hz automatic movement and 30-bar water resistance. Longines calls carbon strong and light, but its product listings do not publish a measured weight—so “lightweight” describes the material choice, not a verified gram figure.
What the Ultra-Chron Carbon is—and what “low-weight” means
Longines presents the Ultra-Chron Carbon as a modern expression of its high-frequency watchmaking, drawing on the Ultra-Chron Diver introduced in 1968. The brand says this is the first time it has used carbon in a watch case. The case combines titanium and carbon and measures 43 mm across, according to Longines’ US product listing.
| # | Preview | Product | Price | |
|---|---|---|---|---|
| 1 |
|
THE LONGINES Master Collection 42MM Automatic Watch | $4,300.00 | Buy on Amazon |
| 2 |
|
LONGINES Spirit Zulu Time 39MM Automatic Watch | $3,450.00 | Buy on Amazon |
| 3 |
|
The LONGINES Master Collection 42MM Automatic Watch | $4,400.00 | Buy on Amazon |
| 4 |
|
LONGINES Legend Diver 39MM Automatic Watch | $3,850.00 | Buy on Amazon |
Longines’ announcement describes carbon as “an innovative material that is both strong and light.” That supports a material-led description of the watch as lightweight, but not a claim about its actual mass: the official product information reviewed does not state a weight. Independent launch coverage describes the case as carbon composite and reports a thickness of 14 mm; those details are not given on the official product listing cited here. Longines US product listing; Longines announcement; Hodinkee launch coverage
How the high-beat movement works
Inside is Longines’ self-winding calibre L.836.6. It beats at 36,000 vibrations per hour, equivalent to 5 Hz, and has a power reserve of up to 52 hours. The movement uses a monocrystalline silicon balance-spring. A higher beat rate means the oscillator completes more cycles per second; it does not, by itself, establish how accurate a particular watch will be in daily wear.
Quick wins for a faster PC:
Scan for outdated or missing drivers - takes under a minuteDriver Scan →Clear out junk files and repair common Windows errorsFree Scan →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →#1 Best Overall
- Automatic L687 movement, hours, minutes, small seconds with 24 hours indicator at 9 o'clock. date indicated by the half moon central hand. Moon phase display at 6 o'clock. Case, hours, minutes, small seconds with 24 hours indicator at 9 o'clock. date indicated by the half moon central hand. Chronograph mechanism : central 60 seconds hand, moon phase display with 12 hours counter at 6 o'clock, 30 minutes counter with day and month display at 12 o'clock. Transparent case back with sapphire crystal
- Stainless steel with triple safety folding clasp and push-piece opening mechanism
- 5 Year International Warranty
Longines-distributed press material says the silicon balance-spring and other components make the movement “up to ten times more resistant to magnetic fields than the ISO 764 standard.” This is the brand’s stated comparison, not an independent magnetic-resistance test result. Longines US product listing; Longines-distributed press material
Chronometer certification and the stated test process
Longines-distributed press material says the finished watch is certified as a chronometer by TIMELAB under ISO 3159. It describes a 15-day qualification process in several positions and at three temperatures: 8°C, 23°C and 38°C. That description is attributable to Longines; no TIMELAB certificate for this specific reference was independently reviewed here. Certification is distinct from a claim that every individual watch will keep the same time under every owner’s conditions.
Rank #2
- Automatic L844 movement, hours, minutes, seconds and date. 24 hours hand with time zone mechanism
- Beige Leather strap with double security folding clasp with micro adjustment system
- 5 Year International Warranty
Case, dial, strap and water resistance
The official listing specifies a screw-in crown, water resistance to 30 bar, and a scratch-resistant sapphire crystal with anti-reflective coating on both sides. Those are product specifications, not evidence of independent dive-use testing. The watch’s 1968 Ultra-Chron Diver lineage and 30-bar rating make its aquatic positioning understandable, but the available evidence does not establish performance in a particular dive or operating conditions beyond the published rating.
The dial is anthracite with Swiss Super-LumiNova. Longines lists a nylon strap and titanium buckle. The combination keeps the focus on a technical sports watch while the use of carbon distinguishes the case from a conventional all-metal construction. Longines US product listing; Longines product specifications
Rank #3
- Automatic L687 movement, hours, minutes, small seconds with 24 hours indicator at 9 o'clock. date indicated by the half moon central hand. Moon phase display at 6 o'clock. Case, hours, minutes, small seconds with 24 hours indicator at 9 o'clock. date indicated by the half moon central hand. Chronograph mechanism : central 60 seconds hand, moon phase display with 12 hours counter at 6 o'clock, 30 minutes counter with day and month display at 12 o'clock. Transparent case back with sapphire crystal
- Stainless steel with triple safety folding clasp and push-piece opening mechanism
- 5 Year International Warranty
How it connects to the 1968 Ultra-Chron Diver
Longines traces the current model to its 1968 Ultra-Chron Diver, describing the older watch as part of the brand’s history of high-frequency timekeeping and calling out its distinctive cushion-shaped case. The Carbon carries that heritage forward through its high-beat movement and sports-watch specification, while introducing a titanium-and-carbon case. This is the manufacturer’s account of the lineage rather than an independent assessment of design continuity. Longines announcement; Longines product history
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Price and market availability
At the time the cited pages were checked, Longines listed the watch at $5,550 on its US site and £4,550 on its UK site. These are market-specific listed prices observed at that time, not a global price guarantee; current pricing, stock and availability can change. Check the local official listing for the latest information. Longines US listing; Longines UK listing
Quick Recap
Rank #4
- Automatic L movement, hours, minutes, seconds. Screw-down case back
- Stainless steel with double security folding clasp with micro adjustment system
- 5 Year International Warranty
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.
