F# 13sus4, 1st inversion (B in the bass)
Also written as F#13sus4/B.
Notes, from the bass up
B (bass)C#EG#D#F#
The same notes as F# 13sus4 (B, C#, E, G#, D# and F#), rearranged so B is the lowest note. Use it to move between chords with smaller jumps across the keyboard.