Small Size Automatic
The Grand Seiko automatic caliber 9S27 strikes that difficult and delicate balance between high performance and slimness. The latest Spron alloy is used for the balance spring and both the pallet fork and escapement wheel are made by MEMS engineering.
|Winding mechanism||Automatic with manual winding mechanism|
|Mean daily rate*1||+8 to -3 seconds per day|
|Normal usage accuracy||+10 to -5 seconds per day|
|Power reserve||Approximately 50 hours|
|Vibrations||28,800 vibrations per hour (8 beats per second)|
|Number of jewels||35 jewels|
- 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.
Caliber 9S27 Models
9S Mechanical Movement
The three movements at the heart of Grand Seiko
One of the world's foremost mechanical movements, the culmination of high-precision micro-engineering and the attention to detail of Seiko's expert watchmakers.
Spring Drive is a unique movement that delivers one-second-a-day precision, using just the power of a mainspring.