This practical complication indicates the date, day of the weeks and the month. The changing face of the moon reproduced on the dial adds a poetic note. The reproduction of the lunar cycles on the dials of Blancpain complete calendar watches evokes the time-honoured ties between watchmaking and astronomy. Sapphire Case Back Under Lug Correctors Dial window material type: antireflective-sapphire Case diameter: 40.0 millimeters #15,601,970 in Clothing, Shoes & Jewelry ( ) #26,339 in