The most striking feature of the Aquatimer Perpetual Calendar Digital Date-Month Edition “50 Years Aquatimer” is the matte black Ceratanium® case. A team of specialists at IWC worked for more than 5 years to develop this new material, which is based on a titanium alloy. A special manufacturing process gives the metal a black, ceramic finish. As light and robust as titanium, Ceratanium® is also as hard and scratch-resistant as ceramic. Furthermore, the material boasts high skin tolerance and corrosion-resistance. The watch features a black dial to complement the case, while the self-winding IWC-manufactured 89802-calibre has several components which are finished in black, including the rotor. The integrated digital perpetual calendar displays the date and the month with large digits in the style of a digital watch. It recognizes leap years and the different lengths of the months. The chronograph with flyback function displays stopped times combined in a totalizer at 12 o’clock.