Description: Material: The guitar fret file is made of carbon steel and wood material, which is great, and the handle is designed to be comfortable to holdEasy to Use: Fret crowning edges file is convenient to use, with 4 different sizes grooves for different frets(1mm,2mm,3mm,4mm), cater to your varieties of requirementsApplication: Guitar fret trimming metal files for guitar repair and maintenance4 Crowning Grooves: 1mm grooves are suitable for narrow frets, such as ukuleles; 2mm grooves are suitable for all standard guitars, basses, banjos, and mandolins; 3mm and 4mm grooves are suitable for jumbo fretsAccessory Tool: Guitar Fret Crowning Dressing File is great for luthiers, guitarists, hobbyists, DIY enthusiasts, DIY frets and basses Specification: Material:carbon steel and wooden Size Chart: length:22.7cm/8.94inch Package Includes: 1 Guitar Fret Crowning File withGasket Note: Please allow slightly errors due to manual measurement and different monitors.