In 2015, the Year of the Portugieser, IWC’s newly developed annual
calendar is another interesting additional feature to
complement the perpetual calendar.
The complication is
powered by the new IWC-manufactured 52850 calibre.
Both are found for the first time in the Portugieser Annual Calendar
(Ref. 5035).
The Portugieser Annual Calendar is available in 18-caratred gold (Ref. IW503504) with a silver-plated dial or in stainless steel with a silver-plated (Ref. IW503501) or midnight blue (Ref. IW503502) dial.
Source: IWC Schaffhausen