The Tudor Black Bay GMT S&G is a model with multiple time zones, a highly functional complication that establishes local time without losing sight of the time in two other time zones. Recognisable by its 24-hour graduated rotating bezel with two colours, representing day and night, the Black Bay GMT S&G also gives a subtle aesthetic nod to the history of this watchmaking function.
1. Satin-brushed and polished case in 316L stainless steel and yellow gold, 41 mm in diameter, with a bidirectional rotating bezel in yellow gold and insert in black and brown anodised aluminium as a hallmark of the GMT function
2. Domed grained matt black dial
3. “Snowflake” hands, a hallmark of TUDOR divers’ watches introduced in 1969, with Grade A Swiss Super-LumiNova® luminescent material
4. Manufacture Calibre MT5652, COSC-certified with a silicon balance spring, 70-hour power reserve
5. A choice of three bracelet designs: black Jacquard fabric, aged brown leather or riveted 316L steel and yellow gold
6. Five-year transferable guarantee with no requirement for registration or periodic maintenance checks
The Manufacture Calibre MT5652 with built-in GMT function was developed by TUDOR for the Black Bay GMT S&G model. It illustrates the technical development process which is unique to TUDOR, drawing on adaptable architecture capable of including new functions into its manufactured movements rather than resorting to additional modules. A minor detail for some, but a must for watchmaking purists.
It has been designed to ensure robustness, longevity, reliability and precision, as has its variable inertia balance, which is maintained by a sturdy traversing bridge with a two-point fixation. Together with its non-magnetic silicon balance spring, the Manufacture Calibre MT5652 is certified as a chronometer by the Official Swiss 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.
Another notable feature is that the power reserve of the Manufacture Calibre MT5652 is “weekend-proof”, about 70 hours, which enables the wearer to take the watch off on a Friday evening and put it back on again on Monday morning without having to reset it.
41 mm steel case with polished and satin finish
48-notch bidirectional rotating bezel in yellow gold with 24-minute graduated matt brown/black anodised aluminium disc
Yellow gold screw-down crown, with the TUDOR rose in relief, with circular satin-brushed steel winding crown tube
Domed sapphire crystal
Waterproof to 200 m (660 ft)
Riveted steel and yellow gold bracelet with polished and satin finish, or brown leather strap with steel folding clasp and safety catch, or black fabric strap with beige band and buckle
Manufacture Calibre MT5652 (COSC)
Self-winding mechanical movement with bidirectional rotor system
Swiss Chronometer officially certified by the COSC (Swiss Official Chronometer Testing Institute)
Jumping hours (second time zone), 24 hours, minutes and seconds at the centre
Instantaneous date at 3 o’clock without non-correction range synchronised on the jumping hours hand
Stop-seconds for precise time setting
Variable inertia balance, micro-adjustment screw
Non-magnetic silicon balance spring
Frequency: 28,800 beats/hour (4 Hz)
Power reserve of approximately 70 hours