9S MECHANICAL MOVEMENT

AUTOMATIC 3-DAY POWER RESERVE GMT

Caliber 9S66

AUTOMATIC 3-DAY POWER RESERVE GMT

Caliber 9S66

Caliber 9S66 has all the performance of the most standard automatic movement of the 9S mechanical models — Caliber 9S65 — but comes with the addition of the GMT function.

Pulling the crown out by one notch enables the hour hand to be adjusted without stopping the second hand so that the highly accurate timekeeping delivered by the Hi-Beat 36000 is not lost.
The watch is the embodiment of the Grand Seiko pursuit of high accuracy, maintaining exceptional precision in both the essential time display and the GMT function.

SPECIFICATIONS
Driving system Automatic with manual winding mechanism
Accuracy
(when static)
+5 to -3 seconds per day

Note: This accuracy is the result of measuring the loss/gain of the time for seventeen days before the inside movements of the watch are put in the case. The measurement has been done in the factory where temperatures or position of the movements are controlled.

Normal usage accuracy +10 to -1 seconds per day
Power reserve Approximately 72 hours
Vibrations 28,800 vibrations per hour (8 beats per second)
Jewels 35 jewels
Remarks Dual time function with 24-hour display

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 incorporates the latest technology alongside its breadth of craftsmanship to raise the art of watchmaking to its peak.

CALIBER 9S66 MODELS

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