The Oyster Perpetual GMT-Master is the watch for airline pilots, chosen by serious travellers and professionals who fly the world. The GMT-Master, introduced in 1955, was developed to meet the needs of international pilots. The GMT-Master II, unveiled in 2005, has proved to be even more invaluable to those whose professions involve long-distance travel. Featuring a rotatable 24-hour graduated bezel and a separate 24-hour hand, it allows those who travel the world to read three different time zones. Two simultaneously.