When the GMT-Master was launched in 1954, Pan American Airlines, who was the original party that approached Rolex to develop a watch which could simultaneously display the exact time in two different time zones, immediately adopted it. In order to differentiate between watches intended for its crew and for ground staff, a special order with white dials was manufactured for ground staff. Probably fewer than 200 of these white dial watches were made, and they are a rare find today.