Features: Made from solid wood material, sturdy and durable. The felt material is soft and wear-resistant, without damaging the keys. Used for removing hardened hammer felt to restore the tone. The S-shaped elbow design is easy to polish and durable. Suitable for piano repair technicians, music school students, piano enthusiasts and other groups who need to repair worn keys. Can be used in piano repair studios, music classrooms, home piano maintenance centers, and other places. Great Tool for sanding or polishing. Specifications: Material: Sandpaper and Solid Wood Size: Approx. 15.5x2cm/6.10x0.79inch Package Includes: 2pcs Piano Hammer Sandpaper File Tool 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.