Rolex applied for the patent for the Prince movement in 1926 and it was granted in October 1927. The advantage of this rectangular movement was that you could place the winding barrel and the balance at opposite ends of the movement, therefore the winding barrel and balance could be made much larger in order to improve the accuracy. Up until this design had been patented, the mechanical movement was fitted into a circular case, with a much smaller winding barrel and balance in order to fit inside the case.

The Prince was one of the most accurate wristwatches made up to this date. The accuracy of the watch comes from the very high quality balance wheel, which used solid gold screws to add extra weight thus giving the wheel much more momentum. The movement had very high quality finishing to the escapement, even the wheels, which ensured the accuracy of the Prince movement.

The Prince is also nicknamed the "doctor's" watch. Many believed this was due to the use by doctors of the Prince as their wristwatches, however, Rolex publicized the Prince being suitable for medical professions and the Prince was often given to doctors by grateful patients.

The present Prince is a fabulous example in absolutely original, crisp condition. The Rolex crown and case number are extremely crisp to the case back and can be seen easily with the naked eye. The hallmarks to the left of the crown is deep, crisp and untouched. The champagne dial is original, unrestored and finishes this doctor's wristwatch beautifully.