In this system, besides the shock absorber of the movement, the whole movement assembly is float mounted by means of an elastic anti-shock ring made of synthetic rubber (see illustration on the left). This robustness was further improved with the "DS" System (meaning “Double Security”). The 25-651 is the most prevalent Certina movement which was used in countless models, where it proved its robustness. The 25-65 or 25-651/652 (with date/day and date) was launched in 1960, and was 1mm slimmer than the predecessor 28-45. Hamilton saw a need to add automatic wristwatches to their line but they had no such movements.Īt the end of the fifties, the demand for flat wristwatches was increasing, and Certina developed an applicable movement. In 1954, Certina began providing Hamilton with self-winding movements, and did so for a few years. Maybe you had already noticed: the first number in the movement designation stands for the diameter in millimetres. The 28-45 movement line was launched in 1953 and had the same construction characteristics as the previous movement, except that the diameter was 3mm bigger. Finally, in 1951 with the 25-45, the first Certina-developed self-winding movement came onto the market.
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The first self-winding movement with a rotor (the KF 21-0114 movement, introduced in 1950), was derived from the AS 1323 movement. Various manual-winding movements were in the product range until 1947 when the first self-winding movement – the hammer-winding KF 360 – came out. These were sold in Switzerland and France. In 1888, when the Kurth brothers founded their company called Kurth Frères, only watch parts and movements were produced.