1972 Tressa Chronograph automatic cal. 11.
The movement is based on the Buren 1282 with micro rotor and was not designed to attach a chronograph mechanism – this led to the crown at 9 o’clock. While the el Primero has survived until today, the expensive design made this movement a victim of the quartz boom. Consequently, the number of these watches with the crown on the wrong side is pretty low.
Tressa was a popular watch brand in the 60-70s. However, like many others, the Tressa disappeared because of the quartz crisis.