The Seiko caliber 8S21 (aka 8S21A) is a 3-hander, no-date solar powered quartz watch movement. It has 2 jewels and...
8S21
The Seiko caliber 8S23 (aka 8S23A) is a solar powered quartz watch movement with a day/date. It has 2 jewels...
8S21
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Recent Comments
My Hamilton chronograph: With the crown pointing horizontally out – minus 2 seconds a day.…
You will encounter countless issues trying to do this: the holes in the dial won't…
Horrible movement. Mine was running -40 per day, almost 1ms beat error. Had it serviced,…
Does anyone know if this caliber is actually an in-house Cartier caliber, or is it…
I do get a little tired of having to guess the ins and outs of…
Fantastic movement, this series of movements from eta are one of the best imo.
Hi Bobmartens, the chart has been updated. Please see the section "Caliber 763 VS 763E"…