The E-sharp dominant seventh flat five chord (abbreviated "E#7(b5) chord") is a four-note chord consisting of the notes E♯, G, B, and D♯. The chord is formed by lowering the fifth of a E-sharp dominant seventh chord a half step.
E-sharp dominant seventh flat five chord
E♯ G B D♯
1 3 ♭5 ♭7
tetrad (four-note chord)