Timekeepers Club / September 8, 2023

Blancpain Fifty Fathoms 70th Anniversary Act 1 for Only Watch

Blancpain has been an enthusiastic donor to and supporter of the Monaco Association Against Muscular Dystrophy for more than two decades. For the Association's Only Watch 2023 Auction, as Blancpain has been celebrating the 70th Anniversary of its iconic Fifty Fathoms which publicly debuted in 1953, it is fitting that it has created a special edition – featuring a unique blue-themed colour motif – of the Fifty Fathoms 70th Anniversary Act 1 timepiece launched earlier this year.

The patrimony of the Fifty Fathoms is legendary. Its creator was Blancpain’s then Co-CEO, Jean-Jacques Fiechter, who drew from his own experience as a pioneer diver. His insights were profound, as the combination of functions and features he invented have come to define diving watches for the entire watch world ever since. A testament to the clarity of his vision was the adoption of the Fifty Fathoms by the world’s leading navies including France, Germany, Norway, Israel and the United States, to name but a few. From 1957 to 1959, when the U.S. Navy conducted its rigorous testing programme to select its diving watch, pitting the Fifty Fathoms against other Swiss and American models, only the Fifty Fathoms passed all the tests. Summarising its decision to choose Blancpain, the Navy concluded:

In summary, experience with 12 Blancpain underwater watches during Operation HARDTACK yielded virtually complete satisfaction. No worthwhile suggestions for improvement of this watch can be offered.

This special edition of the Fifty Fathoms 70th Anniversary Act 1 for Only Watch has been inspired by the 1953 original Fifty Fathoms as well as two other landmark editions: the 2003 50th Anniversary Fifty and the 2007 Fifty Fathoms, which marked the birth of the new generations of this icon. The DNA of all three shines through this unique edition with its blue unidirectional bezel featuring a domed shape ensuring exceptional visual depth and made of sapphire with its extraordinary scratch resistance; its subtle blue-gradient dial with darker outer rim and luminous indexes – Arabic numerals at 3, 6, 9, and 12 o’clock and baton-type hour-markers at the five-minute marks – each fashioned from multiple layers of Super-LumiNova® to bestow extra depth; its Blancpain movement 1315 featuring three mainspring barrels, giving the timepiece a reliable five-day power reserve, as well as a free sprung balance fitted with a silicon hairspring, for greater precision and robustness.

The clear caseback offers a view of the movement’s high-end finishing, extra-large jewels and 18-carat gold winding rotor, coated with a NAC platinum-based alloy and bearing the inscription “Only Watch Blancpain”. The stainless steel case features the same 42.3 mm size recently launched on the Fifty Fathoms 70th Anniversary Act 1.

The watch is fitted with a blue NATO-style strap made of nylon reclaimed and recycled from fishing nets removed from the sea as part of environmental ocean clean-up efforts.

Technical specifications

Blancpain Fifty Fathoms 70th Anniversary Act 1 for Only Watch

Reference: 5010-1140-NAOA

Unique Piece for Only Watch 2023


  • Material: Stainless steel
  • Diameter: 42.30 mm
  • Thickness: 14.30 mm
  • Glass: Sapphire crystal and sapphire crystal caseback
  • Unidirectional sapphire bezel
  • Water-resistant to 300 meters (30 bar)

Dial and hands

  • Blue-gradient dial
  • Applied indices with Super-LumiNova®
  • Pencil hour and minute hands coated with Super-LumiNova®


  • Caliber 1315
  • Automatic mechanical movement
  • Diameter: 30.60 mm
  • Thickness: 5.65 mm
  • Number of parts: 227
  • Number of jewels: 35
  • Power reserve of 120 hours
  • Specialities: 18-carat gold winding rotor with the inscription “Only Watch Blancpain”


  • Hours, minutes, seconds, date

Strap and buckle

  • Blue nylon NATO-style strap


  • CHF 20'000 – 30'000  
  • USD 22'000 – 33'000 
  • EUR 20'600 – 30'900 

For more information, please visit


Leave a comment

You must be logged in to post a comment Login / Sign up