Family: 1B4 jewels
The Seiko caliber 1B21 a solar radio signal movement found in ladies size Seiko watches. It is has a basic 3-hander no-date layout.
Last updated 8 Oct 2026Suggest a correction
TECHNICAL SPECIFICATIONS
Movement Type
Solar
Jewel Count
4 jewels
Display Type
Analog
Winding
Solar
FEATURES
Hacking Seconds
QUICK FACTS
BRAND
TYPE
SolarSTATUS
In ProductionMANUFACTURE
In-houseCALIBER FAMILY
1BCOUNTRY
JapanALSO KNOWN AS
cal. 1b21seiko 1b21
FOR WATCH DEALERS
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Watches with this movement
Seiko
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SSDY047
SolarSteel
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SSDY049
SolarSteel
Seiko
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SSDY053
SolarSteel
Seiko
Seiko Selection
SWFH089
SolarSteel
Seiko
Seiko Selection
SWFH090
SolarSteel
Seiko
Seiko Selection
SWFH117
SolarSteel
Seiko
Seiko Selection
SWFH118
SolarSteel
Seiko
Seiko Selection
SWFH122
SolarSteel
Seiko
Seiko Selection
SWFH142
SolarSteel
Seiko
Seiko Selection
SWFH145
SolarSteel
Seiko
Seiko Selection
SWFH146
SolarSteel
Seiko
Seiko Selection
SWFH148
SolarSteel