Chord sequence
D7 G7 C7 A♭7 B♭maj7
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 G major
Over D7 · V7
Mode 5 of Major
Over G7 · V7/IV
Over C7 · IV7
Mode 4 of Melodic Minor
Over Ab7 · ?
Mode 6 of Blues
Over Bbmaj7 · ♭IIImaj7
Mode 4 of Major