The Blancpain Villeret ref: 6638-3431-55B features a 42mm platinum case with a white dial. This timepiece is powered by the automatic winding Blancpain caliber 3863, introduced in 2004. It includes a perpetual calendar function, displaying the date, month, and leap year, along with a moonphase indicator. Additionally, the watch incorporates an equation of time complication, providing precise timekeeping adjustments.