This year, Revolution turns 20. Two decades of chronicling watches, people and ideas have given us a front-row seat to a remarkable story: how an age-old craft has both preserved its soul and reinvented itself for the 21st century. To celebrate, we’ve chosen over 100 names and milestones that, for us, define the era so far. From leaders to watches, you can see the whole list here.

The Récital 28 Prowess 1 is a milestone in watchmaking, as it addresses a problem that is neither theoretical, abstract nor aesthetic but stubbornly real, in a complication that has always aspired to be useful. World time watches promise universality, but the fiction on which they rest, that the relationship between a city and its offset from Coordinated Universal Time (UTC) is constant, has never survived contact with the messy reality of Daylight Saving Time.

Bovet Récital 28 Prowess 1 (©Revolution)

Daylight Saving Time (DST) is one of those inventions that seemed innocuous when it was first imposed during World War I, a bureaucratic convenience meant to stretch daylight hours and save energy. A century later, it has become an enduring nuisance for anyone trying to keep track of the correct time across time zones. Some countries observe it; others do not. Where it is observed, the start and end dates vary. In a world time watch, this means that for nearly half a year, many of the cities on a world time dial are effectively displaying the wrong time.

Most makers have chosen to live with the contradiction. At best, the names of cities that shift under DST are printed in a different color. More elaborate approaches exist: the Glashütte Original Senator Cosmopolite can show any of 37 time zones and indicate whether each is Standard or Daylight Time, but such solutions apply only to a single chosen zone.

The Bovet Récital 28 Prowess 1 is the first mechanical watch to treat the problem globally. The watch divides time into four timekeeping systems: Coordinated Universal Time, American Summer Time, European and American Summer Time and European Winter Time. Selecting one with the crown instantly reconfigures the display so that everyone of the 24 reference cities shown is aligned with reality.

The watch divides time into four timekeeping systems: Coordinated Universal Time, American Summer Time, European and American Summer Time and European Winter Time (©Revolution)

The means by which this is done is as ingenious as it is complex. In place of a city disk, the watch carries 24 rollers, each with four faces. At rest, they function like a conventional world time dial, lining up with a rotating 24-hour ring. But when the pusher in the crown is pressed, the roller at 8 o’clock indicates the new system, and all 24 rollers advance together by 90 degrees. The set of cities on view changes dynamically. At the heart of the mechanism is a huge central wheel cut with two sets of teeth. Around its lower edge, radial toothing couples it to the selector train. Above that, a ring of conical teeth engages horizontal pinions connected to each roller. When the selector is activated, the gear turns and every roller moves in unison.

The watch with a city disk which carries 24 rollers, each with four faces (©Revolution)

The Prowess 1 is also a perpetual calendar, with the date and month displayed on rollers flanking a double-sided flying tourbillon at 12 o’clock. The date is retrograde, a complication usually managed with a lightweight hand but here executed with a rotating drum. To manage inertia, Bovet developed a rectilinear rack and helical spring. As the rack advances daily, it stores energy, which is then released at the end of the month in a single decisive return stroke. A retractable finger on the rack engages the month star only during that stroke, advancing it by one step. A safety device was developed so that the perpetual calendar cannot be corrected during the dead zone when the indications are in the process of changing.

The perpetual calendar with the date and month displayed on rollers flanking a double-sided flying tourbillon at 12 o’clock (©Revolution)

Seen from the back, the movement is extensively open-worked and hand engraved. Power comes from a single oversized barrel, providing 10 days of reserve which is impressive, given that the same source has to drive not only the calendar rollers but also a flying tourbillon.

The open-worked and hand engraved movement (©Revolution)

In the end, what makes the Récital 28 Prowess 1 significant is not just that it solves DST but also how it does so. It demonstrates that even in an area as well-worn as the world timer, there are still problems worth solving and still solutions that only mechanical ingenuity can provide.

Tech Specs: Bovet Récital 28 Prowess 1

Movement Manual winding Caliber R28-70-00X; 10-day power reserve
Functions Hours and minutes; small seconds on flying tourbillon; world time display on rollers with UTC, American Summer Time, European and American Summer Time, and European Winter Time; perpetual calendar with rollers for retrograde date, month, leap year and day
Case 46.3mm × 17.85mm; Grade 5 titanium, platinum or 18K red gold; water resistant to 30m
Dial Open-worked, with inner and outer ring in aventurine; rollers in black PVD
Strap Double-face full skin alligator with folding clasp