Bringing this mechanical computer over to the QP Balancier, we finally get a watch that’s focused purely on the perpetual calendar complication and its ingenuity. This new release “only” has a few indications — hours, minutes, seconds, power reserve, day of the week, oversized double-digit date, month, leap year cycle, a 24-hour disc with day/night indications, calendar year (located on the caseback), and the current selected function for the crown. Simple, right? The movement shows off the ability to be adjusted at any time of day, while a red zone on the 24-hour disc indicates the danger zone. But not to worry, the mechanical computer locks the user out anyway during the danger zone. You can’t damage it.