The Portugieser Perpetual Calendar Tourbillon combines two sophisticated complications of Haute Horlogerie. The tourbillon, made up of 82 individual components, weighs only 0.635 grams. The tourbillon - literally "whirlwind, vortex" - causes the balance wheel to rotate around its axis inside a cage, compensating for the effects of gravity and increasing precision. The perpetual calendar, which does not require any correction until 2100, automatically recognizes the different durations of the months and leap years. The indication of the moon phases is so precise as to present a one-day difference after 577.5 years. The IWC-manufactured automatic caliber 51950 offers a 7-day power reserve. The case is made of 18 carat Armor Gold® gold. Thanks to a modified microstructure, this material has a decidedly higher hardness than traditional gold alloys. The blue dial, the golden hands and the applied indexes in 18-karat gold highlight the nautical style of this special edition, limited to only 50 copies and on sale exclusively at the IWC Boutiques. The timepiece is accompanied by a blue alligator leather strap.