Warner's U.S. copyrighted GUITAR HARMONIC TUNING  F A C F A D.
It is like blowing notes of a HARMONICA.
They are all in Harmony.

The 6 strings of a guitar are also in harmony when just 1 string is pressed with 1 finger, while strumming.

The easiest way ever invented to play a guitar using only one finger. Especially great for smaller and older hands!

• There are 9 different chords using 1 finger

• (1 flat is the key of "AF")

• FOUR 1 FINGER CHORDS (C, C7, F, & A7)

• ONE 3 FINGER CHORD (G7)

• You just press string 1 or 2 or 3 or bridge 1 & 2 or 1,2 &3