In 1952, the world's first chronograph with an aerial slide rule was born. By writing numbers on the bezel and dial of the watch and operating the chronograph and bezel based on the navigation slide rule invented by US Navy Colonel Wiems, the calculation of `` fuel calculation '' `` rise and fall time '' can be done It is now possible. This feature is popular with professional people, including pilots. The hero of space history called Mercury 7 astronaut Scott Carpenter also wore to space. The first model was certified as the official watch of the World Pilots Association AOPA and, through its 60-year history, has become one of the most functional, timeless and one of the few items that represents the 20th century.