Grand Seiko
GS 9SA5
Direct impulse · introduced 2019
Beat rate
36,000 vph
Power reserve
80h
Jewels
36
Introduced
2019
Escapement
Direct impulse
The 9SA5 is Grand Seiko's flagship mechanical movement, introducing the Double Impulse Escapement that directly drives the balance wheel on both impulse strokes. This architecture reduces friction and improves accuracy without silicon components. Combined with Hi-Beat 36,000 bph, 80 hours of power reserve, and Zaratsu-finished bridges, it represents the apex of Grand Seiko's mechanical work.
Specifications
Beats per hour
36,000
Jewels
36
Power reserve
80h
Diameter
31.3mm
Height
5.18mm
Escapement
Direct impulse
Introduced
2019
Finishing
Haute horlogerie
Service interval
3 years
Service cost tier
Luxury
Complications
datequickset
Known service issues
- Service must be performed by a Grand Seiko authorized center; the Double Impulse geometry requires factory-trained calibration
- Three-year service interval is shorter than many competing luxury movements
Notable in
- Grand Seiko Elegance Collection SLGH005 (White Birch)
- Grand Seiko Sport Collection SLGA011
Buying advice
Practical guides for buying a watch with this caliber on the pre-owned market: