Which Swiss watch brand is known for its pilot's watches like the Mark XI?

The Swiss watch brand known for pilot’s watches such as the Mark XI is IWC Schaffhausen.

IWC—short for International Watch Company—was founded in Schaffhausen in 1868 by American watchmaker Florentine Ariosto Jones. Although the company makes several important watch families, its identity is especially associated with aviation watches designed for legibility, precision, durability, and resistance to magnetic fields.

The Mark XI, introduced in 1948, became one of IWC’s defining models. It used the company’s Caliber 89 hand-wound movement and was designed around demanding navigation requirements. Its black dial, clear markings, central seconds hand, and anti-magnetic inner case made it a practical instrument rather than merely a decorative luxury watch.

The Mark XI is often confused with IWC’s Big Pilot’s Watch, but they are different historical models. The Big Pilot’s Watch was a large observation watch associated with the 1940s, while the Mark XI was a more compact military-navigation watch. IWC’s later Mark-series and Pilot’s Watch models continue to draw on this functional design language. The brand is Swiss, despite its American founder and the international meaning of its name.