Throughout its history, IWC Schaffhausen has engineered numerous mil-spec watches for different branches of the British military. These service watches were characterized by high-precision movements, extreme ruggedness, a functional design with easily legible dials, and purpose-built technical features. The Spitfire Pilot's Watches reflect this chapter of the brand's history. The Big Pilot's Watch 43 Spitfire features the typical Big Pilot's design with the striking conical crown in an ergonomic 43-millimetre case, combined with a distinct military aesthetic. The case, case back, and crown are made of lightweight and robust grade 5 titanium. The dark grey matte color results from an elaborate surface treatment in which the components are first polished and then sandblasted. The design of the black dial was inspired by historical observation watches. Only the minutes and seconds are printed in white on the outer ring, while the hours appear smaller and in a more discreet grey print on the inner circle. This layout made it easier for pilots and navigators to read off the minutes and seconds at just a glance. The striking 'field watch' design is complemented with a brown calfskin strap in contrast stitching. The timepiece also features IWC's new EasX-CHANGE system, allowing the wearer to change the strap quickly and easily at the touch of a button. At work inside the case is the IWC-manufactured 82100 calibre movement. The Pellaton winding system, reinforced with ceramic components, builds up a power reserve of 60 hours. A soft-iron inner case protects the movement from the effects of magnetic fields.