Guitar Chord Chain for playing the custom chord progression. Guitar Chord Construction Algorithm: Over 500000 Guitar Chords. ▷ Three types of the 3D-Hand Model for displaying 3D-Fingering Model. ▷ 4-Part 4-Voices and 5/6-Voices Chords: Accomp. /Harmonic Chords toggle key on the Keypad. ▷ Auto-correction + Auto-guiding Keypad.