This is a set of 9 pcs understring radius gauge set, includes 7.25", 9.5", 10", 12", 14", 15", 16", 17" and 20" radius, you can choose according to your demands. Fast, accurate nut bridge saddle and string adjustment. Suitable for electric guitar, wood guitar, acoustic guitar. You can have a try. Features: Fretboard measured in radians, and radians to adjust the strings piano code. Fast, accurate nut bridge saddle and string adjustment. Obtain accurate measurements of your instrument's fretboard radius,saddle radius nut radius from either theupper or the bottom radius surface. These come in the most popular fingerboard radius and make it easy to measure the radius from either above or below the strings. Stainless steel material, smooth surface and rounded off edge, easy using and very convenient. Total 9 pcs a set, 7.25", 9.5", 10", 12", 14", 15", 16", 17" and 20" radius, you can choose according to your demands. A must have tool for bass guitar maintain and adjustment. Suitable for electric guitar, wood guitar, acoustic guitar, acoustic guitar setup. Specifications: Name: Understring Radius Gauge Material: stainless steel Color: silver Item weight: 42g / 1.48ounce Package size: 80 * 80 * 20mm / 3.15 * 3.15 * 0.79in Package weight: 42g / 1.48ounce Package List: 1 * Understring Radius Gauge Set