IWC's Da Vinci Perpetual Calendar IW3755-05 boasts a unique blend of white ceramic and yellow gold in its case, complemented by a sleek silver dial. This model first made waves in 1985 when it introduced the world to the brand's iconic perpetual calendar mechanism. It quickly gained acclaim for its innovative design and became the most widely sold perpetual calendar in the industry. Its success led to adaptations in other IWC models and even in watches by JLC. The 39 * 14.3mm case features hinged lugs and was available in a variety of metals and dial colors. The option for a sapphire crystal was also available upon request. The 3758, its successor, was released around