Description Late 20th century Case: 18 carat gold, 36 mm diameter Bracelet: leather strap with 18 carat gold original Rolex clasp Dial: gold-coloured with sapphire glass and date loop Functions: Day-Date Reference number: 1803 Serial number: 4151825 Movement number: DD 949306 Caliber: 1556, automatic Gross weight approx. 67 g Movement not tested Note: The Rolex Oyster Perpetual Day-Date is a self-winding chronometer manufactured by Rolex. Initially presented in 1956, the Day-Date was the first watch to display the date as well as the day, spelled in full. The calendar display is offered in 26 languages.