In music theory, a Flat symbol indicates that a note is lowered by one semitone. On the guitar fretboard, this corresponds to moving one fret down (towards the headstock) from the natural note.
How to enable Flats
To enable flats in an Official Tab, follow these steps:
• Open an Official Tab and switch to Chords view
• Click the Gear icon
• Toggle Use Flats to the on position
The tab will immediately refresh to display the notation using flats.