About D'Addario Lemon Oil Cleaner and Conditioner:
 
D'Addario Lemon Oil is a natural cleaner and conditioner formulated to remove dirt, grease, and build-up from unfinished woods on all string instruments. It's particularly recommended for use on fretboards. Lemon Oil also helps to condition your instrument to resist dryness which can prevent cracks and extend its life. For dark, unfinished woods only.