Based on the manual winding Nomos Alpha movement, the Delta adds an unusual and patented date display. Typically, a date wheel and associated gears are stacked below the mainplate between the rest of the watch movement and the dial. However, this makes these movements more bulky and thick. Instead, Nomos places the date ring around the movement, with the switching mechanism integrated into the movement itself, making the Delta and Beta just as thin as the Alpha, on which they are based.
The power reserve indicator is also integrated into the bottom plate of the movement, adding no additional thickness. It shows the remaining power in the mainspring, serving as a reminder to wind the watch.
This calibre is part of a family of manual winding movements:
- Nomos Alpha (small seconds)
- Nomos Beta (small seconds, date)
- Nomos Delta (small seconds, date, power reserve)
- Nomos Gamma (small seconds, power reserve)