The ETA 2783-F6 watch movement, which was manufactured between 1966 and 1970, features an indirectly driven minute and automatic gear that is integrated into the movement. This design allows for a low profile. The movement also includes a ratchet on the dial side and a crown mechanism with a rocker bar. Additionally, it incorporates a rather small rotor ball bearing. Unfortunately, there is no available information on the differences between the 387 and 389 models. The ETA 2783-F6 movement offers automatic winding, a sweep second hand, and a quickset date function.