From one time zone to another, at the push of a button

The Hublot Unico manufacture movement is equipped with a new patented proprietary module which enables the second time zone to be updated instantly by a push-button, allowing the local time to be read easily via the conventional main hand of the watch. The time at home is indicated using a second arrow-shaped hour hand, which integrates a day/night indicator and is set us ing the crown. Today, we board an aircraft like we were getting in a car, traveling constantly back and forth between time zones. GMT has proven to be one of the most useful and frequently used complications, hence the need to simplify its operation and make it easier to read.

The ingenuity of the module developed by the Hublot manufacture resides in its simplicity. A patented invention which provides a simple solution to a complex, practical indication. The Big Bang Unico GMT is a watch with an original aesthetic and optimum legibility, combined with the ability to update the second time zone very quickly, with the time corrected at the push of a button.

Simplifying the GMT operating principle

The two push – buttons adorning the Big Bang Unico GMT case are not the same as those seen on a chronograph. Their aesthetic has been redesigned to ensure they can be distinguished, and their rectangular shape brings to mind the historic push – buttons of the first Big Bang models. Each press of the push – button at 2 o’clock moves the time forward by one hour; the one at 4 o’clock moves it back. A safety device prevents simultaneous activation of the two push – buttons. GMT time (local time) is set independently o f the other hands by pressing a push – button; the gears for the minutes and seconds are not driven. This means it is not necessary to synchronise all of the hands with every change in time zone.

 Optimising legibility

The two time zones occupy the same dis play space on the dial, ensuring they provide optimum legibility. Local time is indicated via the main hand. A fourth hand, which is arrow – shaped, indicates the time at home using a 12 – hour display, and is correlated to a day/night disc so that the user can tell at a glance whether it is 5am or 5pm. The graduations for the 12 hours are alternated: engraved on the dial and index ed on the bezel. This practical element also lends the piece its distinctive identity.

In a 45 mm case, the Big Bang Unico GMT is available in a titanium or carbon fibre version, on a structured, ribbed black and blue natural rubber st rap. Both versions are equipped with the ingenious “One Click” interchangeable strap system. The UNICO movement has been redesigned to transform it into a calibre with an integrated GMT function , boasting a 72 – hour power reserve.


  • References: 471.NX.7112.RX (Titanium), 471.QX.7127.RX (Carbon)
  • Case: Satin-finished and polished titanium or carbon fibre, diameter 45mm, thickness 15.85mm.
  • Case-back: Satin-finished and polished titanium or carbon fibre, sapphire crystal
  • Crystal: Sapphire crystal with anti-reflective treatment
  • Bezel: Satin-finished and polished titanium with Dual Time engraved or Carbon fibre with Dual Time inscribed in white lacquer, 6 H-shaped titanium screws
  • Lateral Inserts: Blue composite resin with titanium screws
  • Water Resistance: 100M or 10ATM
  • Dial: Skeleton blue and anthracite grey (Titanium) or skeleton blue and matte black (Carbon)
  • Movement: HUB 1251, UNICO self-winding movement, developed and manufactured in-house by Hublot
  • No. of components: 339 (41 jewels)
  • Frequency: 4 Hz (28,800 Vib/h)
  • Power Reserve: 72 hours
  • Strap: Titanium deployant buckle or Carbon fibre and black PVD titanium deployant buckle

More information on the GMT titanium click here, for the GMT in carbon fire, click here.