Oris bc4 flight timer as its name suggests is the perfect tool for aviators it is equipped with oris 690 automatic calibre a modification of eta 2836 2 the movement performs 28 800 vibrations per hour and has 30 bearing jewels a 38 hour power reserve is available for the convenience of the wearer the timepiece provides information about two separate time zones a date display is positioned at the 6 oclock mark two subsidiary dials are available one displaying hours and the other one