Seiko Caliber 3B21 No technical information found for this movement.Watches with the 3B21 movement3B21-0AA03B21-0AB03B21-0AC03B21-0AD03B21-0AE03B21-0AF03B21-0AG03B21-0AH03B21-0AJ03B21-0AK03B21-0AL03B21-0AM03B21-0AN03B21-0AP03B21-0AS03B21-0AT03B21-0AV03B21-0AW03B21-0AX03B21-0AY03B21-0AZ03B21-0BA03B21-0BB03B21-HAA03B21-HAB0