The revolutionary new tool fretbar understring leveler lets you level your frets under full tension without removing the strings. You can level your frets with the strings ON.Material: Aluminum - CNC machined. High glossiness, durable and long-lasting use, not easy to deform.Cuboid shape. Dimensions:Convenient luthier sanding leveler file.Applicable for fret, saddle, and fingerboard sanding, great accessory for players and luthiers. Suitable for the fret leveling of electric guitar, acoustic guitar, electric bass, banjo, mandolin, etc.Colour:BlackMaterial:Aluminum alloySize:Length: about 23cmPackage Contents:1* Fretbar Understring LevelerOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.