Spring driven with lever escapement and balance (two springs – for hour movement and alarm clock), 21 jewles. Incabloc shock protection device. Manual winding. Caliber AS 1475.
On the housing side are two crowns. The one at the 2 o'clock hour in the basic position is used for winding the alarm, and when pulled out deactivates the alarm. In the same position the alarm time is set by turning the crown in the opposite direction of clockwise and the alarm is activated. Crown in position 4 in the basic position winds the clock, in the raised position adjusts the time.
Caliber AS 1475 was produced from 1954 to 1970, a total of about 780 000 pieces. The Rado company logo, as found on the dial with a line that stretches below the name was used in the period from the 1951 to 1957/8. In the fifties of the 20th century the logo is printed and subsequently embossed. These facts suggest datation between 1954 and 1957/8.