Black Bay Fifty-Eight Bronze 39mm (Ref: M79012M-0001), Black Bay Fifty-Eight 925 39mm (Ref: M79010SG-0001, M79010SG-0002) and 18K (Ref: M79018V-0001), Pelagos 39 (Ref: M25407N-0001), Black Bay 36 S&G (steel and gold TT)
The Tudor caliber MT5400 is a true no-date (ND), 3-hander automatic movement with 27 jewels and a beat rate of 28,800 vph (4Hz). This manufacture movement is a Certified Chronometer (COSC), equipped with a bidirectional rotor system and variable inertia balance, micro-adjustment by screw. This caliber also features a non-magnetic silicon balance spring.
MT5400 VS MT5402:
There is a similar Tudor caliber MT5402 with the main difference being that the MT5400 discussed on this page is a slightly enlarged version of the MT5402 (~30.3mm vs 26mm). The reason for the larger diameter of the MT5400 is purely cosmetic, due to the fact that watches powered by this caliber (such as the 925 and gold Black Bays) feature an exhibition style caseback.
In Tudor’s own words:
“Together with its non-magnetic silicon hairspring, the Manufacture Calibre MT5400 is certified as a chronometer by the Swiss Official Chronometer Testing Institute (COSC), with its performance going beyond the standards set by this independent institute. In fact, where COSC allows an average variation in the daily running of a watch of between -4 and +6 seconds in relation to absolute time in a single movement, TUDOR insists on between -2 and +4 seconds’ variation in its running when it is completely assembled.”
From the Black Bay Fifty-Eight 925 marketing materials:
From the Pelagos 39 marketing materials (essentially the same as above):
The MT5400 is another movement that some label as an in-house movement, but Tudor themselves refer to as a manufacture movement. Even more confusion comes about due to the fact that calibers such as the MT5400 are manufactured by Kenissi (not exactly Tudor), but Kenissi is owned in part by Tudor (Chanel being the other part). This just means that the movement wasn’t 100% designed and produced entirely by Tudor itself, but and outside supplier – that happens to be owned by Tudor.
Watches with this movement:
The Tudor calibre MT5400 is found in the Tudor Black Bay Fifty Eight Bronze (introduced in June 2021), the Fifty-Eight 925 and 18K (introduced in April, 2021), as well as the Pelagos 39 (announced in 2022).