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What is the TUDOR Pelagos FXD Marine Nationale?
TUDOR describes the Pelagos FXD as developed in conjunction with French Navy combat swimmers. The original Marine nationale specification, reference 25707B/21, is a satin-finished titanium watch with a navy dial and a bidirectional bezel. TUDOR’s current English product page presents the watch under reference M25707B/26-0001. These designations should not be treated as interchangeable without checking the exact product listing.
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Tudor Pelagos FXD Automatic Chronometer Blue Dial Men's Watch m25707kn-0001 | $4,249.99 | Buy on Amazon |
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TUDOR Pelagos FXD CHRONO | $4,879.99 | Buy on Amazon |
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Tudor Pelagos Chronometer Black Dial Titanium Men's Watch M25600TN-0001 | $5,399.99 | Buy on Amazon |
For the original 25707B/21, TUDOR specifies a 42 mm case, 12.75 mm thickness and 52 mm lug-to-lug length. The case has a steel caseback and sapphire crystal, and is rated to 200 m (660 ft) water resistance. Those are manufacturer specifications, not independent test results. See TUDOR’s original 25707B/21 specification sheet.
What does FXD mean on the Pelagos?
FXD refers to the fixed bars machined into the titanium case, where a conventional watch would usually have removable spring bars. TUDOR says the fixed-bar construction is intended to increase robustness and reliability. It also affects strap choice: ordinary spring-bar straps should not be assumed to fit, and compatibility needs to be confirmed for the exact FXD configuration.
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- Featuring a Blue Band, Black Case, Scratch Resistant Sapphire Crystal
- Display Type: Analog
- Item Shape: Round
What is the Pelagos FXD bezel used for?
TUDOR specifies a bidirectional rotating titanium bezel with a ceramic disc and retrograde 60-minute graduation for navigation by successive stages. In TUDOR’s description of the Marine nationale method, the wearer aims to reach a planned objective from the sea without surfacing, following an underwater route planned in advance. The bezel’s stated role is to support that staged navigation use; the sources do not establish that the watch replaces a dive computer, navigation training or other equipment. Read TUDOR’s Pelagos FXD and Marine nationale explainer for its account of the intended method.
Movement and published specifications
The original reference 25707B/21 uses TUDOR Manufacture Calibre MT5602, an automatic mechanical movement with a bidirectional rotor. TUDOR lists it as COSC-certified and specifies approximately 70 hours of power reserve. The following details come from TUDOR’s original product sheet:
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- Tudor Pelagos FXD Chronograph Cycling Automatic Black Dial Men's M25827KN-0001
- Central hours, minutes and seconds hands, with stop-seconds.
- Variable-inertia balance with micro-adjustment screw and a non-magnetic silicon balance spring.
- Frequency of 28,800 beats per hour (4 Hz) and 25 jewels.
- Approximately 70 hours of power reserve.
TUDOR’s current English product page for M25707B/26-0001 continues to list the MT5602 (COSC), approximately 70 hours of reserve, 200 m water resistance, a 42 mm titanium case and the navigation bezel. These published specifications do not amount to independent accuracy, durability or underwater-performance testing.
Straps, fit and what comes in the box
The original 25707B/21 sheet lists a navy fabric strap with self-gripping fastening and a second navy rubber strap with a woven motif and titanium buckle. TUDOR’s current product page also describes a navy fabric strap and identifies an included rubber strap. Since the fixed bars constrain attachment, check the exact reference and configuration before buying a replacement; the available product information does not establish compatibility for specific aftermarket straps.
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- Tudor Pelagos Chronometer Black Dial Titanium Men's Watch M25600TN-0001
Which reference should you look for?
The original specification sheet identifies the Marine nationale watch as 25707B/21, while TUDOR’s current English page displays M25707B/26-0001. For purchase decisions, confirm the reference, included strap configuration, local availability and guarantee terms on the relevant regional TUDOR page or with an official retailer. TUDOR’s current English page states a five-year transferable guarantee without registration or periodic maintenance checks; confirm that the terms shown apply to the specific watch and market you are considering. View TUDOR’s current English Pelagos FXD product page.
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.
