The Seiko caliber 78A is a vintage time-only quartz movement manufactured in Japan. It uses an SR927SW battery. The movement includes a trimmer condenser for frequency adjustment and is commonly found in watches with dial or case codes beginning with 7800.
Last updated 15 Sep 2026Suggest a correction
TECHNICAL SPECIFICATIONS
Movement Type
Quartz
Display Type
Analog
Winding
Quartz (Battery)
QUICK FACTS
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