C#maj13 chord

The C-sharp major thirteenth chord (abbreviated "C#maj13 chord") is a seven-note chord consisting of the notes C♯, E♯, G♯, B♯, D♯, F♯, and A♯. The chord is formed by adding a thirteenth to a C-sharp major eleventh chord.

In practice, the fifth (G♯) and eleventh (F♯) are often omitted from the C#maj13 chord to avoid a very dissonant sound, and because it's not always possible to play all notes simultaneously.