It was 75 years ago that two Portuguese gentlemen inspired IWC to create a watch that could match the precision of a marine chronometer. The resulting innovative Portugieser family of IWC watches has seen many complications grace its movements, and to mark this anniversary, IWC has launched the new Annual Calendar, which showcases an all new in-house calibre. This 44.2mm stainless steel model features a midnight blue sun-ray dial, with a white printed railway minute track and Arabic numerals. The three windows of the annual calendar are located between 11, 12 and 1 o'clock, indicating the month, date and day of the week. A seconds sub-dial is found at 9 o'clock, while the 7-day power reserve indicator is at 3 o'clock. Time is told by classic slim feuille hour and minute hands. The new Swiss-made automatic Annual Calendar movement, calibre 52850, only requires altering, via the crown, once a year in the shorter month of February. This elegant IWC timepiece is worn on a black Santoni alligator leather strap and secured by a stainless steel clasp.