A Patek Philippe open face pocket watch, crown wind, circular white dial with Roman and baton numerals, subsidiary seconds at six, signed case, dial and movement, 18 jewels, three (3) heat, cold isochronism, adjusted to five (5) positions, no 860880, signed Patek Philippe & Co, Geneve, Swiss, case reference 417940, in platinum. Diameter 4.5 cm.