Guitar chords in the key of A# or Bb:
Chord Bb7sus4 (8th fret) notes: Bb, F, Ab and Eb. You must leave out the 6th and 5th strings.
Bb(A#) dominant 7th suspended 4th chord's alternative names: Bb7sus, Bb7sus4.
1(A#/Bb), 4(D#/Eb), 5(F), b7(G#/Ab).