C# Sixth chord (C#6) on the guitar fretboard

The C# Sixth chord (C#6) is made of C# (the root), E# (major 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 sixth chord adds a major sixth to the major triad, giving four notes with no seventh. The same notes appear in the minor seventh chord a sixth higher, so the neck shows two names for one shape. It sits between the plain major triad and the major seventh.