18-jewel Cal.21 rhodium-plated movement monometallic balance adjusted to 6 positions shock-absorber self compensating flat balance-spring Ivory-coloured dial with luminous indexes subsidiary dials for the days of the month days of the week and date 4 apertures for the leap years and gold ring aperture in blue for the gold moon phases luminous white gold hands polished and brushed case the bezel fluted in a circular pattern case back with 6 screws straight lugs gold screwed bars 4 pushers on the band for quick date change fitted leather strap with 18ct white gold Gerald Genta buckle case dial and movement signed 38mm.