This Type of structure has a long history at Patek, dating back to your early nineteen sixties Together with the ref. 2597 Travel Time Calatrava. As James Stacey described in his Fingers-On Along with the 5164R in 2019, the movement during the 2597 originated within the intellect of Louis Cottier https://www.watchesworld.com/germanys-top-10-favourite-luxury-watches/