Caliber 9SA4
9S MECHANICAL MOVEMENT
Manual-winding Mechanical Hi-Beat 36000 80 Hours
Caliber 9SA4
Today, the ritual of winding a watch is one of life’s pleasures.
The simple act of turning the crown taps into the senses to forge a deeper connection with time’s natural flow. In the 1960s and ’70s, manually wound 10-beat Grand Seiko creations were manufactured in the pursuit of better rate stability and higher precision. This year, for the first time in more than 50 years, Grand Seiko announces a new hand-wound high-beat movement, Caliber 9SA4.

SPECIFICATIONS
Note: *Mean daily rate is a mean value of daily rates in a condition where the movement before assembly in a case is measured in six positions in a fixed manner under artificially controlled environment for 12 days.
· Twin barrels
· Power reserve indicator
A thoroughly redesigned and reconstructed movement based on Caliber 9SA5
As with Caliber 9SA5, the new 9SA4 beats 10 times per second while achieving a power reserve of 80 hours when fully wound thanks to its highly efficient Dual Impulse Escapement and two barrels. Both movements use the Grand Seiko Free-sprung Balance and a hairspring with overcoil. As a result, Caliber 9SA4 benefits from the rate stability, resistance to outside interference, and high performance that have long characterized Grand Seiko’s high-beat movements. And, as with other Grand Seiko mechanical movements, 9SA4 is tested in six positions at three different temperatures over 17 days to ensure it meets the Grand Seiko Standard.
What makes 9S Mechanical special?
The concept of Grand Seiko was born from the desire to build the world's best watch, and the collection continues to push precision in mechanical watches to the limits of timekeeping technology.
As a true manufacture, Grand Seiko combines the latest technology with hand craftsmanship to raise the art of mechanical watchmaking to the highest possible level.

