Manufacturer | Miyota (Citizen) |
Caliber Number | 0S21 aka OS21 |
Type | Quartz |
Replaces Caliber | Citizen 0510 |
Diameter | 13.50”’ (30.80mm) |
Height | 5.10mm |
Battery Cell Number | SR927W |
Frequency | 32,768Hz |
Quartz Type | Tuning fork type quartz crystal |
Stem | 065-453 |
Hand Sizes | 120/80/18 |
Jewels | 0 |
Functions | Hours, minutes, central chronograph seconds, 60 minute counter, 24 hour hand, date |
Country of Manufacture | Japan |
Known Models | REC, Philip Stein Active Chronograph |
The Miyota caliber OS21 is a quartz watch movement with zero jewels. It is made in Japan.
Accuracy Rating
Miyota states the accuracy of this movement to be +/-20 seconds/month.
Additional Resources:
- Official instruction manual (pdf)
- Movement specs from Miyota
- Buy a replacement OS21 movement here
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