MusicNomad Diamond U-File MN 813, precision tool for dressing individual frets, wide diamond coated file to quickly and efficiently lower and level the fret height to match adjacent frets, ideal for partial preparation of individual frets on guitars, banjos, mandolins and ukuleles, suitable for all bass frets, except the first 5 frets closest to the nut, unique, ergonomic shape offers ultimate comfort and control, the special U-shaped channel design allows you to level the frets even when the strings are mounted, notches on the top and arrows on the side provide the location of the diamond coated filing area, precision made with 1.50 mm (0.059‘) thick stainless steel and hand lapped (+/- 0.00125’/ft) to meet tight specifications and avoid any deformation, each set includes 3 sizes: 3.2 cm (1.25‘), 5.1 cm (2’) and 7.6 cm (3’), all edges are deburred and/or rounded for a soft feel, convenient hanging hole, incl. storage sleeve, Note: The fret file is not suitable for working on stainless steel frets. The extreme hardness of the material can damage the diamond coating of the file. Please note that this is not a valid reason for exchange or complaint if the file becomes defective after use on stainless steel frets.