With the introduction of Black Bay, Tudor has successfully submitted yet another Black Bay model for tests to obtain a Master Chronometer certification, as part of a constant bid to improve the quality of its products. This is the third application of this standard to a watch in the Tudor collection, and a step towards a future where the entire collection is METAS certified.
METAS Master Chronometer certification is comprehensive and covers the main functional characteristics of a watch including precision, resistance to magnetic fields, waterproofness and power reserve. Its standards are incredibly high, starting with precision. In order to qualify, a watch must be able to function within a 5-second range of variation each day (0 +5), that is to say 5 seconds less than the Swiss Official Chronometer Testing Institute (COSC) (-4 +6) carried out on a single movement and a second less than TUDOR’s internal standard, which is applied to the brand’s models with a Manufacture Calibre (-2 +4). The certification also guarantees the timekeeping accuracy of a watch subjected to magnetic fields of 15,000 gauss. Finally, it also guarantees that the waterproof capability claimed by the manufacturer conforms with the International Organization for Standardization (ISO) standard 22810:2010, as does the power reserve of each Master Chronometer watch. It should also be noted that two prerequisites are necessary before the certification can be obtained: Swiss manufacturing must conform with the criteria of Swiss Made, and the movement must be certified by the Swiss Official Chronometer Testing Institute (COSC).
All the tests and prerequisites leading to the Master Chronometer certification, which the Black Bay has achieved, are summarised below:
Certification by the Swiss Official Chronometer Testing Institute (COSC)
Precision at two temperatures, in six different positions and at two different levels of power reserve: 100% and 33%
Smooth functioning when exposed to a magnetic field of 15,000 gauss and precision following exposure
Waterproof to 200m (660 ft) in accordance with ISO standard 22810:2010
70-hour power reserve
The Manufacture Calibre MT5602-U, which powers the Black Bay, displays hour, minute and seconds functions. It offers the general look and feel of Tudor Manufacture Calibres with dedicated sun laser design and bears the Master Chronometer mention on its bridges, emphasising its distinctive performance. Its rotor is fashioned in tungsten monobloc and is openworked. It also features the distinctive laser radial grooving with sand-blasted details. Its bridges and mainplate have alternate sand-blasted and polished surfaces and laser decorations.
Its build is designed to ensure robustness and precision. To do this, the variable inertia balance wheel is maintained by a sturdy traversing bridge with two-point anchoring. This system together with its non-magnetic silicon hairspring, means the Manufacture Calibre MT5602-U is able to function within a tolerance range of 5 seconds (0/+5) tested on a fully assembled watch.
In its latest iteration, named Black Bay, the case keeps the original proportions of a 41mm in diameter case with a thinner profile. The unidirectional rotatable bezel offers very prehensible sides and its insert shows subtly curved numerals aligning with the outline of the outer ring. However, the aesthetic details don’t stop at case dimensions and bezel. The seconds hand recalls the look of the early diving watches of the brand with a lollipop design while the satin black dial is subtly radial-brushed for a very subtle shine under direct light. Ergonomics have evolved as well, with a redesigned crown, reminiscent of the curves found on the crowns of the brand’s historical technical watches, that is set flush to the middle case band so that its tube is not visible.
The Black Bay comes fitted with either an entirely satin-brushed three-link steel bracelet or a five-oval-shaped-link brushed and polished steel bracelet, both complete with the “T-fit” clasp equipped with a system for rapid length adjustment. Easy to use, requiring no tools and offering five positions, this practical system allows wearers to carry out a fine, instant adjustment of the total length of the bracelet along an adjustment window of 8mm. The clasp features ceramic ball bearings that ensure a smooth and secure closure in addition to adding a pleasing tactile element to the action of the clasp.
A black rubber strap option is also available for the Black Bay. The strap comes in three sizes complete with Tudor “T-fit” clasp, and for the perfect fit, it is able to be cut down to the exact size of the wearer’s wrist. On the inside it features the signature snowflake motif for added grip, and it is form-fitted specifically for the Black Bay.