Enter Caliber 9F. Introduced in 1993, Grand Seiko’s 9F movement combined an accuracy rating of +-10 seconds a year with the high torque of a mechanical movement and a low level of energy consumption. It debuted a number of innovative features that were new for a quartz watch. The Twin Pulse Control Motor allowed for the use of Grand Seiko’s long, heavy hands; a backlash Auto-Adjust Mechanism eliminated any shuddering of the seconds hand as it advanced across the dial, ensuring accuracy; an aged and highly-stabled quartz crystal paired with an IC programmed to specifically respond to that crystal’s reaction to temperature changes; and an Instant Date Change Mechanism.
The 9F series continues to power Grand Seiko’s quartz line. In 2018, the brand introduced a GMT complication with an independent hour hand via Caliber 9F86. And 2020 saw the introduction of Caliber 9F85, which allows for an independently adjustable hour hand without the addition of a GMT complication.