Basic (hour-minute) handwound movement with 18 jewels and a total of 117 parts. Hallmark of Geneva certified.
Work on its development began in 1952 in L’Ile (the building on the Rhone River ‘island’ that has housed Vacheron Constantin’s historical premises since 1875) and it was presented for the brand bicentenary celebrations in 1955 under the name Calibre 1003.
Its 9-lignes or 21.05 mm diameter and 1.64 mm thickness have made it the world’s smallest mechanical manual-winding movement on the market. By way of comparison, this micromechanical masterpiece composed of 120 parts is about the size of a small Swiss 20-centime coin.
This now legendary calibre (of which the excellence was to be confirmed by the subsequent orders placed by other great names in fine watchmaking) was used to equip three round watches that set a new record as the world’s thinnest watches measuring just 4.54 mm thick