The Portugieser Perpetual Calendar Tourbillon unites two sophisticated Haute Horlogerie complications. The tourbillon, made of 82 individual parts, weighs only 0.635 grams. The "whirlwind" causes the balance wheel to rotate around its own axis, compensating for the effect of gravity on the oscillating system and increasing accuracy. Requiring no correction until 2100, the perpetual calendar automatically recognizes the different lengths of the months and leap years. The moon phase display is so precise that it will deviate by one day only after 577.5 years. The self-winding IWC-manufactured 51950 calibre boasts a power reserve of 7 days. The case is made of platinum. The silver-plated dial and the rhodium-plated hands and appliqués harmonise wonderfully with the rare precious metal. Limited to 50 pieces, the timepiece is fitted with a blue alligator leather strap from the Italian shoe manufacturer Santoni.