C Quartal (So What), 2nd inversion (Bb in the bass)
Also written as C quartal/Bb.
Notes, from the bass up
Bb (bass)DGCF
The same notes as C Quartal (So What) (Bb, D, G, C and F), rearranged so Bb is the lowest note. Use it to move between chords with smaller jumps across the keyboard.