calibre 51010, follower of cal. 50010, replaced by cal. 51011 => 3.00 Hertz / small second-indication
calibre 51011, follower of cal. 51010 => 3.00 Hertz / small second-indication / new cogging
calibre 51110, follower of cal. 50110, replaced by cal.51111 => 3.00 Hertz / central second-indication
calibre 51111, follower of cal. 51110 => 3.00 Hertz / central second-indication / new cogging