C Minor Sixth chord (Cm6) on the guitar fretboard
The C Minor Sixth chord (Cm6) is made of C (the root), Eb (minor third), G (perfect fifth) and A (major sixth). The fretboard shows every one of them across the neck in standard tuning (E A D G B E), and plays them back so you can hear the chord.
The minor sixth adds a major sixth to the minor triad, which keeps the dark third and lifts the top note. Its four notes repeat across the neck and share a shape with the half diminished chord on a different root. It sits next to the minor triad and the minor seventh.