Anti-rust material: rocker and notched ruler are made of stainless steel, which is and can be used for a long time, and it is not easy to scratch guitar. Keep guitar neck straight: Guitar ruler, string leveling tool and guitar string ruler can help you measure whether fretboard is straight and check final height after you readjust or replace fretboard. Wide range of uses: height ruler helps to measure slot, string height, nut and pickup pole piece, and even slot depth. The notched ruler helps to check whether each fretboard is at same level, and fret rocker can span 3 frets and check whether frets are at same level. Nice gift: These guitar luthier tools are excellent gifts for guitar technicians and guitarists, helping them to maintain and repair instruments by themselves in a short time and reduce buzzing; suitable for electric guitars, acoustic guitars, basses, banjos and folk guitars, etc. Color:As Shown Material:Metal Package Contents: 1 * neck ruler 1 * plastic ruler 1 * 2-hole triangle ruler 1 * sticker Only above package content, other products are not included. Note: Light reflection and different displays may cause color of item in picture a little different from real thing. The measurement allowed error is +/- 1-3cm.