The Breitling Montbrillant Datora ref. A2133012 with the white dial is a mechanically complex chronograph rooted in the brand’s aviation heritage. It features a 43mm stainless steel case with a bidirectional slide rule bezel, a hallmark of Breitling pilot watches, designed for performing flight-related calculations. The silver dial is densely configured, offering a full calendar layout with day and month apertures at 12 o’clock, a pointer date indicated by a central hand with a red crescent tip, and chronograph subdials arranged in a classic tri-compax style. Powering the watch is the Breitling Calibre 21, based on the Valjoux 7751 automatic movement, providing approximately 42 hours of power reserve. The movement supports not only the chronograph function but also the calendar and a 24-hour indicator, making it notably more intricate than standard chronographs.