MusicNomad S FILE Safe Zone Guitar Fret Crowning FileA TRUE GAME CHANGER: Designed by our Sonoma, CA team and in collaboration with top repair techs, the Safe Zone S File sets a new higher standard for what you should expect when you buy a Fret Crowing File. No detail is overlooked, and it is packed with unmatched features and benefits. WHY DID I NOT THINK OF THE SAFE ZONE?: The patent pending Safe Zone innovation prevents you from overfiling. At the top of the file, there is a small strip where there