Minor 7 flat 5 (m7b5) chords are less common than dominant, major or minor 7ths, but it is still essential to learn them as they are important for moving between keys (e.g., from major to relative minor) and for II V Iprogressions in minor keys. Here are some of the most commonly used m7b5 chord shapes.
x F#m7b5
F#m7b5
Bm7b5
Bm7b5
x Em7b5
Em7b5