Breguet Marine Hora Mundi 5557

Breguet's Marine Hora Mundi 5557, reference 5557BB/YS/BW0, is a GMT watch in white gold measuring 43.9 mm across. The case stands 13.8 mm thick with lugs set 24.5 mm apart, and a sapphire crystal covers the hand-guilloché blue dial. Inside is the self-winding calibre 77F1, giving 55 hours of power reserve and driving a dual time zone function alongside central seconds and a date display. The screw-down crown and pusher allow the second time zone to jump instantaneously without disturbing the running time. Hands are treated with luminous coating for legibility in low light. A sapphire case back exposes the movement's bevelled and straight-grained finishing. The watch is fitted to a white gold bracelet with a folding clasp, and Breguet rates the case to 100 metres.