ITEM NAME:4Pcs Stainless Steel Guitar Notched Radius Gauge Design Fingerboard Fretboa O3V2 4Pcs Stainless Steel Guitar Notched Radius Gauge Design Fingerboard Fretboa O3V2 Notched Radius Gauge design can use with strings on.Include 2 narrow radius gauges and 2 wide radius gauges.Set of 4 pcs stainless steel measuring tool for Guitar fingerboard. Precision laser-cut from .024inch(0.6mm) stainless steel with each being etched with the radius and "NARROW" or "WIDE". Notched radius gauges work with strings on!This new version gauge is handy when you want to check a fingerboard without taking the strings off. The set includes closely-spaced string notches for use near the nut, and wider spacing for use near the body (great for compound radius fingerboards). Type: Guitar Notched Radius Material: Stainless Steel Color: Silver Quantity: 4Pcs(1Set) Size: 87 x 87 x 0.4mm Package contents: 2* 7.25inch guitar ruler 2* 20inch guitar ruler