[EFFICIENT&DURABLE]: fret erasers are made of natural rubber and emery by a special foaming process. The hardness of emery is greater than that of corundum, so the fret polishing is more efficient and more durable.[MULTIPURPOSE]: fret polish eraser can solve problems such as fret file scratches, corrosion/oxidation/rust of frets&string. And it is suitable for the character line polishing of most musical instruments, such as guitar, , ukulele, etc.[SOFT&ELASTIC]: The polishing rubber can effectively fit the filaments and cords, reducing damage to the filaments and cords. It can be cut into different shapes to facilitate grinding and polishing of different metal parts.[MULTI-VALUED]: a set of 100&400&1000Grits. The larger grit number, the finer and brighter polished effect it will be. For more serious rust or oxidation, you can choose a smaller particle size, and vice versa.[EXCELLENT DESIGN]: Good size to adapt to finger force. Clear numerical marks facilitate identification. A variety of color matching and exquisite packaging. BUT KEEP IT FROM KIDS. Because it looks like a delicious .rtable to grip.color:MulticolorMaterial:Rubber + EmeryPackage Contents:3 x Guitar Fret Erasers(1000 /400 /100 )1 x Guitar String Rust Remove PenOnly 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.