In 2011, a few years after the introduction of its in-house-developed-and-produced Caliber 8500-family of movements, Omega introduced the Caliber 9300 chronograph movement, which was also entirely developed and manufactured in-house. This impressively large caliber has the brand’s renowned co-axial escapement, a column-wheel mechanism, and a silicon balance spring. The movement has a 60-hour power reserve. So far, Omega has only used Caliber 9300 in its Seamaster Planet Ocean chronographs and Speedmaster Caliber 9300 watches, including the Speedmaster “Dark Side of the Moon.” Caliber 9300 has a two-register layout in which the subdial at 3 o’clock shows both the recorded hours and minutes. This subdial can also be used as a second-time-zone indicator if used cleverly.