Based on the so-called 'jumping forward' system, which sets aside a small amount of energy with each click of the date at midnight, the digital display of the date and month is now also being adopted in a model from the revamped Ingenieur collection (celebrated at Sihh 2013 with an adrenalin-fuelled party): the Ingenieur Perpetual Calendar Digital Date-Month. The four-year leap year cycle is also shown in digital form. In correspondence with the date, month and leap year discs, the dial is fitted with semi-transparent sapphire-glass inlays that allow the wearer to admire the interaction of the wheels as they move - an innovative design for this type dear to IWC. The perpetual calendar takes leap years into account, displaying every four years on 29 February and is programmed until 1 March 2100. The case is made of titanium aluminide, which is used in motorsport for pistons and valves as it is a stronger and lighter alloy than pure titanium and is particularly well suited to withstand the extreme temperatures reached in the combustion chamber. The movement is the IWC automatic calibre 89802.
