The Portugieser, which traces its origins back to the 1930s, looks to naval deck watches for its highly legible dial. This new model combines a one-minute flying tourbillon, a retrograde date display and a flyback Chronograph measuring hours and minutes on a single totaliser at 12 o'Clock. In the interests of precision, another quality inherited from marine timepieces, the hacking tourbillon means the movement can be stopped and the time set to the nearest second. Both the pallet lever and escape wheel of the in-house IWC 89900 calibre are treated with Diamond Shell® technology. This produces an extremely hard surface that reduces friction and improves the flow of energy in the movement. The platinum version shown here keeps precise time throughout its 68 hours of power reserve and comes as a limited edition of 50 pieces, as does the execution in 18k Armor Gold®.