Feature:1. Made of metal material, strong and durable, good performance, long service life and easy to use.2. Grindstone is designed to protect your guitar or bass fingerboard from being scratched or damaged during filing and polishing.3. Not only for crowning guitars, but also for electric guitars, acoustic guitars, bass, ukuleles, etc., a good and simple way to crown worn frets.4. Complete tool for your need to adjust any guitarist like electric guitar, bass, ukule, acoustic guitar.5. Can be used for string change, tuning or check string height, perfect for cleaning, maintaining and repairing stringed instruments.Specification:Item Type: Guitar Repair Tool SetMaterial: Metal Package List:1 x Redstone1 x Greenstone1 x Hex File2 x Silver Spacers1 x 2 Holes Triangular Rule