Leadrise® Set of 9 Understring Radius Gauge for Guitar and Bass Setup Luthier Tools for Bridge Saddle Adjustments<div style="text-align: left;"><strong>[Product Information]</strong><ul><li><span class="a-list-item"> 1.Obtain accurate measurements of your instrument's fretboard radius using the bottom radius of the gauge </span></li><li><span class="a-list-item"> 2.Then use the matching top radius of this gauge to determine the proper height adjustment for the bridge saddles. </span></li><li><span class="a-list-item"> 3.Radius gauges come in 9 sizes: 7.25" 9.5" 10" 12" 14" 15" 16" 17" 20" </span></li><li><span class="a-list-item"> 4.These come in the most popular fingerboard radius and make it easy to measure the radius from either above or below the strings. </span></li><li><span class="a-list-item"> 5.Use these to accurately setup your guitar bridge saddles to match the fingerboard radius. </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/41ZHqoJ1HFL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/51yMIPE4-WL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/41Rqofi6a0L.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/21Is7Eju-4L.jpg" noproxy>