The Portugieser Constant-Force Tourbillon Edition “150 Years” stands out as one of the technical highlights in the jubilee collection. This model has a platinum case, a blue dial with a lacquered finish, and rhodium-plated hands. It is available in a limited edition of just 15 watches. For the first time, the new IWC-manufactured hand-wound 94805 calibre, with a power reserve of 96 hours, combines a constant-force tourbillon with a single moon phase display. This moon phase display needs to be adjusted by only one day every 577.5 years. The patented constant-force mechanism disengages the escapement from the direct flow of power from the wheel train, and transmits completely even impulses to the escape wheel. In conjunction with the tourbillon, which compensates for the negative influences of gravity on the watch’s oscillating system, this achieves a very high level of precision.