REF.570 is a classic model of the Cal.27SC. In the classic Calatrava called big Calatrava in the great case of 35 mm. A CAL.27SC 1949-was produced until around 1970. From the design stage was developed as a Center seconds for calibre. Therefore the 4-car and placed center directly, are turning the Center seconds. It is an ideal design with minimal loss of torque transmission. Dial 20 index near the degradation, case's beauty products.