Hosco H-ZONE Understring Diamond Fret Leveling File Set

Hosco H-ZONE Understring Fret Leveling Tool consists of a Set of 2 to cover the entire fretboard. Made of 1mm thick stainless steel and uses replaceable 800-grit diamond abrasive Sheets. **Not Recommended  for use on stainless steel frets   The HOSCO Zone File is a unique tool that allows you to check the fret level while the strings are on and, if necessary, make adjustments with the diamond file on the fly. Four lengths were needed to cover the zone from the low fret to the high fret. For this reason, the Zone files were designed in a trapezoidal shape; two files make one full set. The name “Zone File” is derived from its unique “Z” shape. It aims to check and adjust a specific “zone” of three adjacent frets. The folded edge of the “Z” is used as a straight edge gauge to check fret height, and the 800 grit diamond file in the center of the “Z” flat surface is used to adjust the fret height. The beauty of this tool is you can check the fret level while the strings are  still on! Set the Zone file so that it passes under the strings above the frets to be checked. Select a zone file long enough to span three frets that you want to check. Tilt the zone file so that its edges touch the three frets, and determine if there is any rocking. If there is no rocking, move along and  continue to the check the same way. You can adjust the fret level with the strings on if you find a high fret. If there is any sagging, it means that the center fret is high. So, set the Zone file so that the diamond file surface touches the fret, and gradually sand the fret to adjust it. Depending on the height reduction of the fret, removing the strings and reshaping the fret crown with a crown file might be necessary. Replacement Diamond sheets are also available.