Tanglewood Lemon Oil
Tax included.
Tanglewood say:
GUITAR MAINTENANCE – POLISH AND CONDITIONING
"Usually, the best time for some general guitar maintenance is when you change the strings. This will give you the best access the fretboard and body, without having any strings in the way.
CLEANING AND CONDITIONING THE FRETBOARD
"Once all of the strings are off, wipe the fretboard down with a lint-free cloth to remove dust.
"Then, spray with a fretboard conditioner, such as Lemon Oil.
"Take a clean cloth, and rub away the dirt and grime.
"Wipe the fretboard with a clean, lint free cloth."