En gång i tiden var Certina en av Topdogsen. 28.8 hz. Vilket var ovanligt då. Läs på om Calibern, grym! With the "288"-calibers which were used from 1970, the balance rate has been increased from by then 19'800 to contemporary 28'800 A/h. As a special feature the 25-671/672 had a micro ball bearing mounted cannon pinion and the Certina patented anchor escapement "Clineric 21". The micro ball bearing (see illustration on the right) had a diameter of only 2.2mm and each of the seven mounted balls had a diameter of 0.3mm! For the serial production, a slightly improved version, the 25-681/682 was introduced from 1972. You can identify watches with this movement trough the marking "288" on the dial. The last self developed self-winding movement was the 919/920-1. It came on the market in spring 1976 and was the successor of the legendary 25-65 calibers.