Chord sequence
Cm7♭5 B7♯11
In every key
Four-note rootless voicings in their two forms, with the 3rd or the 7th on the bottom, played over the root.
Heard in C# major
Over Cm7b5 · ♭iø7
Mode 7 of Major
Over B7#11 · ♭VII7♯11
Mode 4 of Melodic Minor