15 jewels42h power reserve18,000 vph (2.5 Hz)
Vintage Swiss hand-wound calibre from the Eterna 520 family, documented in 1940s–1950s watches, with small seconds and the proprietary Eterna-U anti-shock device. Eterna-U has no matching current shock-protection enum. The exact launch year and current database identity of the 520 base are not established.
Last updated 2 Oct 2026Suggest a correction
TECHNICAL SPECIFICATIONS
Movement Type
Manual Winding
Jewel Count
15 jewels
Power Reserve
42h
Frequency
18,000 vph (2.5 Hz)
Diameter
26.5mm
Height
4mm
Display Type
Analog
Winding
Manual
FEATURES
Hand WindingSmall Seconds
QUICK FACTS
FOR WATCH DEALERS
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