Breguet Marine Hora Mundi 5557

Breguet's Marine Hora Mundi 5557, reference 5557BB/YS/9WV, is a GMT watch cased in white gold at 43.9 mm. The case measures 13.8 mm thick, with lugs set at 24.5 mm. A sapphire crystal covers the blue dial, which is hand-guilloché and finished with a galvanic blue coating; the hands carry grey phosphorescence for night-time legibility. Inside is the self-winding calibre 77F1, giving 55 hours of power reserve and visible through a sapphire caseback. The watch combines a second time zone with instantaneous jumping hours, alongside a central seconds display and date. A screw-down crown secures the case, and the alligator leather strap closes with a white gold folding clasp. The screwed crown helps keep the case rated to 100 metres.