Cartier Calibre de Cartier Perpetual Calendar (Reference W7100030) is a men's watch featuring an 18K white gold case and an elegant grey dial. As a perpetual calendar, it is mechanically programmed to correctly display the date, day, month, and often moon phase, accounting for different month lengths and leap years. While further details like movement type, case dimensions, and bracelet material aren't explicitly provided, the watch is in very good condition, showing only minor, intangible signs of wear, and comes complete with its original box and papers.