F m3/B
The F m3 chord consists of the F (Perfect unison) and G# (Minor third) notes, with B as the bass note.

How to play the F m3/B chord
- Play B as the lowest bass note in the left hand
- Find F (Root) on the piano keyboard
- Add G# (Minor third) — 3 semitones above F
- Press all 3 notes simultaneously to sound the F m3/B chord