Big Pilot's Watch Perpetual Calendar. The large dial, developed in the 1980s by former IWC watchmaker Kurt Klaus, makes the calendar information extremely easy to read. The IWC Big Pilot's Watch Perpetual Calendar IW503605 has a stainless steel case, a blue dial, rhodium-plated hands and a blue calfskin strap. The perpetual calendar automatically recognizes different month lengths and leap years and will not require manual adjustment until the year 2100. The calendar module, which is made of only around 80 individual parts, is driven by a single switching impulse from the IWC-produced 52615 caliber. The components of the Pellaton winding mechanism, which can withstand heavy loads, were made of ceramic, which is practically wear-free. When fully charged, the power reserve in both balances is seven days. The intricately decorated in-house movement can be viewed through the sapphire crystal back.
