Understring Radius Gauges. Set of 9, for bridge saddle adjustments
Obtain accurate measurements of your instrument's fretboard radius using the bottom radius of the gaugeThen use the matching top radius of this gauge to determine the proper height adjustment for the bridge saddles. Radius gauges come in 9 sizes: 7.25" 9.5" 10" 12" 14" 15" 16" 17" 20"