Feature: 1. The precise ruler leveling tool can detect whether there is any difference in the height of the piano grid. Perfectly locate irregular character and find the source of character buzz. 2. Polishing stone is a professional tool for polishing saddles, nuts and character. The protective plate is used to protect the fingerboard from being scratched or damaged when scratching and polishing the strings. 3. Three‑sided polished files, it is made of stainless steel, are rust‑proof and durable, efficient and time‑saving, and can be used for decorative grid lines. 4. It is suitable for most piano frame specifications on the market, such as electric guitar, acoustic guitar, bass, ukulele, etc.The file has 3 different sizes of edges, which are used for narrow wire, medium wire and wide wire. 5. The fingerboard protection gasket can protect the guitar or bass fingerboard from scratching or damage during filing and polishing. Convenient and practical. Specification: Item Type: Guitar Repairing Tool Set Material: Stainless steel and oilstone. Package List: 1 x Three Side Grinding File2 x Fingerboard Protection Gasket2 x Polishing Stone1 x Leveling Rule1 x Storage Bag