The D flat fifth chord is a 2-note chord consisting of the notes Db and Ab.
You can see these notes highlighted in the interactive piano chart below.
The chord itself is often abbreviated as Db5.
Chords that are a superset of Db5. The chords include more notes but always Db and Ab.
In case you prefer a non-interactive variant of the chord chart, we've embedded a PNG image below that shows the notes for the the Db5 chord. Feel free to save or share the image as needed.