Features: Guitar fret erasers are made of rubber and emerys by a special foaming process. The hardness of emerys is greater than that of corundum, so the fret polishing is more efficient and more durable. Fret polish eraser can solve problems such as fret file scratches, corrosion/oxidation/rust of frets & string. 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. It is suitable for the character line polishing of most musical instruments, such as guitar, bass, ukulele, etc. Designed for guitar enthusiasts, musicians, and professionals who want to maintain their guitar's performances and appearance. There are a set of 180 & 400 & 1000 Grits. 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. Specifications: Material: Rubber+emerys Size: As Shown in the Picture Grit Model: 180, 400, 1000grit Package Includes: 1x 180Grit Fret Erasers 1x 400Grit Fret Erasers 1x 1000Grit Fret Erasers note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.