In 1985, IWC made waves in the watch world with the introduction of the Da Vinci Perpetual Calendar reference 3570. This watch featured a unique perpetual calendar mechanism, which became widely popular and was used in other IWC watches and even by other brands. The Da Vinci Perpetual 3750, with its 39mm polished Stainless Steel case and Black dial, was one of these models. It also came in different metals and dial colors, with multilingual markings. The default option was plexi glass, but sapphire crystal could be requested. A ceramic version and gem-set options were also available. The watch was later updated to the 3758 model in 2005, with different movements used over