Tap the image to enlarge
Blancpain Fifty Fathoms Bathyscaphe 43.5mm Mens Watch Blue
Ref. 5000-0240-O52A
The Fifty Fathoms traces its origins to 1953, when Blancpain produced what is widely recognised as the first watch purpose-built for professional diving. The Bathyscaphe is the line's more contemporary expression — the same rated depth, the same unidirectional ceramic bezel, but a design language that sits closer to daily wear than to archival recreation. This reference, introduced in 2016, pairs a satin-brushed grey ceramic case with a blue ceramic bezel insert, its Liquidmetal graduation markers fused into the surface so that the dive scale cannot wear away or lift. The calibre 1315 is what separates this from most dive watches at any size. Three barrels in series deliver a five-day power reserve, the silicon hairspring resists magnetic interference without a soft-iron cage, and the movement itself is finished well enough that Blancpain fits a sapphire caseback — an 18-carat gold rotor with dark coating visible through it. Despite the 43.6mm diameter, ceramic keeps the weight down noticeably against an equivalent steel case, and the downward-curved lugs help the 49.7mm lug-to-lug span conform to the wrist rather than bridge it. The sailcloth strap is rubber-lined underneath, which matters after a full day's wear in heat. The buckle is ceramic to match the case — a small detail that becomes obvious once noticed, and whose scratch resistance makes it more practical than it might first appear.
- Reference
- 5000-0240-O52A
- Brand
- Blancpain
- Collection
- Fifty Fathoms
- Case size
- 43.6mm
- Case thickness
- 13.83mm
- Case material
- Ceramic
- Case shape
- Round
- Dial
- Blue
- Crystal
- Sapphire
- Bezel
- Unidirectional rotating
- Movement
- Automatic
- Calibre
- 1315
- Functions
- Date
- Water resistance
- 300m
- Bracelet / strap
- Fabric strap
- Strap colour
- Blue
- Clasp
- Buckle
- Lume
- Luminous
- Condition
- Ex-display
- Retailer
- Mappin & Webb
Additional specifications
- Lug-to-lug
- 49.70mm
- Power reserve
- 120 hours
Learn more about Blancpain
Jehan-Jacques Blancpain registered as a watchmaker in Villeret in 1735, which makes Blancpain the oldest name in the industry by registration date. The dial still carries JB 1735.
The claim comes with an asterisk the house is candid about: production stopped during the quartz crisis. The name was dormant until Jean-Claude Biver and Jacques Piguet bought it in 1983 and relaunched it on a defiantly contrarian promise — there has never been a quartz Blancpain, and there never will be. In a market then convinced mechanical watchmaking was finished, this proved commercially astute as well as romantic.
The technical high-water mark of the modern era came in 1991 with the 1735 Grande Complication, which combined a tourbillon, perpetual calendar, moon phase, minute repeater, and split-seconds chronograph in one wristwatch.
Blancpain's other lasting contribution is the Fifty Fathoms of 1953, developed with French combat divers and predating the Submariner. It established the vocabulary of the dive watch — rotating bezel, high legibility, real water resistance — and remains the collection most buyers know.
The Swatch Group acquired the brand in 1992. The Villeret line continues the classical side of the house: round cases, double stepped bezels, and complications presented without ornament.
- 1735
- Jehan-Jacques Blancpain registers as a watchmaker in Villeret.
- 1953
- The Fifty Fathoms establishes the modern dive watch.
- 1983
- Jean-Claude Biver and Jacques Piguet revive the dormant brand.
- 1991
- The 1735 Grande Complication is released.
- 1992
- Acquired by the Swatch Group.
Also in 6 collections
This watch appears in Back in Stock (4,868), Automatic Watches (1,750), Blue Dial Watches (861), Sports Watches (800), Dive Watches (572) and Pre-Owned, Ex-Display & Vintage Watches (369).
Best of 2 retailers
What the specifications mean
A mechanical watch built to be worn hard and got wet.
Strengths
- 300m water resistance, rated for actual diving
- 49.7mm lug-to-lug keeps the 43.6mm case wearable
- Sapphire crystal, which resists scratching
- 120-hour reserve survives a weekend off the wrist
- Luminous hands and markers for low light
Worth knowing
- 43.6mm sits at the larger end
Blancpain Fifty Fathoms Bathyscaphe alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | 5000-0240-O52A | 81070 | 23492412110001 |
|---|---|---|---|
| Price | £9,520 | £7,550 | £10,700 |
| Case size | 43.6mm | 44mm | 41mm |
| Water resistance | 300m | 300m | 300m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Fabric strap | Rubber strap | Leather strap |
| Power reserve | 120 hours | 46 hours | 60 hours |
| This watch |
|
|
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 300m it is rated for swimming, snorkelling and recreational diving.
Water resistance explainedWill the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Sapphire, mineral and acrylic comparedDoes it need a battery?
No. It is automatic — the motion of your wrist winds it, and there is no cell to replace.
Quartz, automatic and solar comparedHow long does it run for when it's not worn?
About 120 hours fully wound — enough to sit off the wrist over a weekend and still be running.
Will it fit my wrist?
Lug-to-lug is 49.70mm, which suits wrists from roughly 16.5cm (6½ inches) upward.
Lug-to-lug decides fit more than case diameter does.
How to size a watch to your wristIs it a men's or women's watch?
Listed as men's.
Cheapest place to buy
Both Mappin & Webb and Goldsmiths list it at £9,520, so choose on delivery and warranty rather than price.
More Blancpain watches like the Fifty Fathoms Bathyscaphe
In stock, and close on style and price
