21,600 bph. When in doubt for any Seiko movement specs, ask Ranfft:
http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Seiko_6309A
http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Seiko_6309A
Excellent. Thanks for that.21,600 bph. When in doubt for any Seiko movement specs, ask Ranfft:
http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Seiko_6309A