Description: 【Pre-Attached Sandpaper】: This piano hammer sanding tool comes with sandpaper already attached, ensuring immediate usability. The sandpaper(not included) can be easily replaced when needed for continued efficiency 【Versatile Hammer Correction】: Designed to address misaligned hammers, this tuner tool features four different sanding arcs, making it suitable for standard piano hammer maintenance and adjustments 【Compact Design】: With dimensions of 5 x 4.5 x 2 cm, this piano hammers grinding tool is compact and easy to handle, allowing for good control during the sanding process 【Universal Compatibility】: This piano hammer sandpaper file is suitable for most conventional pianos, providing a reliable solution for both professional technicians and DIY enthusiasts looking to maintain their instruments 【Sturdy Construction】: Made from metal material, this piano tuning tool is built to withstand regular use while maintaining its effectiveness over time   Specification: Material: Metal Size Chart: 5cmx4.5cmx2cm/1.97inchx1.77inchx0.79inch Package Includes: 1x Piano Tuning Tool Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.