In Haute Horlogerie there are very few complications as fascinating as the tourbillon. The tourbillon - literally "whirlwind, vortex" - causes the balance wheel to rotate around its axis within a cage. This movement offers an amazing visual spectacle on the dial; in addition, constant rotation reduces the effect of gravity on the oscillating system and increases the precision of the timepiece. The Portugieser Tourbillon Rétrograde Chronograph features a flying minute tourbillon with a "6 o'clock" stop. In addition, the model is equipped with a retrograde date indication and a chronograph with flyback function. Limited to 50 pieces, the case of this watch is in platinum. The silver dial and the rhodium-plated hands and indexes create a perfect combination with this precious and rare metal. The IWC-manufactured automatic caliber 89900 guarantees a 68-hour power reserve. The anchor and the escape wheel make use of the so-called Diamond Shell Technology®, which reduces friction and improves the flow of energy in the movement.