The ETA 2778 watch movement is a jewel-bearing rotor with 23 jewels for enhanced efficiency and precision. It features a detached manual wind mechanism and includes an ingeniously simple power reserve display. This display utilizes the rotation of the barrel arbor and the barrel itself to indicate the difference in rotation, without the need for a complicated differential gear. The movement also offers automatic functionality and a sub second display. The power reserve is around 2 to 38 hours, but it is limited by a banking pin. The stated range of 36 hours is slightly exaggerated, as the actual run time is closer to 34 hours. The ETA 2778 movement was primarily used during the period of approximately 1955.