This Type of structure has a lengthy history at Patek, courting again towards the early 1960s With all the ref. 2597 Travel Time Calatrava. As James Stacey pointed out in his Palms-On Together with the 5164R in 2019, the movement within the 2597 originated through the thoughts of Louis Cottier https://www.watchesworld.com/germanys-top-10-favourite-luxury-watches/