Grade 503, 15 ruby and sapphire jewels unadjusted, manufactured from 1915 to 1919 a total of 5,510 movements in 14 runs make up this grade. Model 4 size 12/14 open faced; bridge movements of medium quality, single roller and patent micrometric regulator.
Observations, The movements have broad striped pattern demaskeening named Hallmark. The size 12/14 movements have a size 12 bridges and size 14 pillar plate and have a stretched enamel dials that are not recessed into the pillar plate, they require special cases.
Description, 15 ruby and sapphire jewels; oreide settings; spring tempered compensating balance with timing screws; hardened and polished steel escape wheel; sapphire pallets and jewel pin; polished gold center wheel; patent Breguet hairspring; micrometric screw regulator; safety screw center pinion; concave and polished winding wheels; safety recoil click; demaskeened broad striped pattern; gold inlay engraving; unusally large dial is a special feature of the watch.