I never paid any attention to using anything at all on the fingerboard of my 1964 Gibson J45, except for a soft cloth, maybe an old dried up guitar polishing cloth years ago (like the 1970's). After I bought a new McSpadden Mountain Dulcimer with an ebony fingerboard, Lynn McSpadden told me to be sure to use Fast Fret "most every time" that I play. I did get the stuff, & I use it when I remember. I have rarely used the stuff on my guitar, cause I keep it in my Mountain Dulcimer case.