Minute repeaters, also known as striking watches, have always been part of Vacheron Constantin’s repertoire. It is known to be one of, if not the most difficult complication to make, but since 1941, the watchmaker has upped the ante by including the complication in ultra-thin movements.

The latest of which is the Caliber 1731; a hand wound movement that measures a mere 3.9mm in thickness. Clad in a 950 platinum case 8.1mm thick and 41mm in diameter, the gongs of the movement have been rearranged to ensure optimum sound amplification, and a flying strike governor has been employed to regulate the hammer blows on the gongs. This special governor was developed in-house and, unlike traditional lever-type governors, functions completely in silence.