The IWC 37524 watch movement, manufactured exclusively for Mido from 1954 to 1960, features a base plate derived from the AS 1131/1132 movement. It offers optional black rhodium plating and the choice of two regulators: the Fonto regulator with a mobile stud carrier and adjustable regulator pin-width, or the Incastar regulator, which boasts a free oscillating hairspring. The Incastar regulator utilizes two rollers to fix the end of the spring, allowing for length adjustment without the risk of isochronism errors typically caused by the gap between the regulator pins. Additionally, the movement includes automatic functionality and a sub-second feature.