String Action Ruler Gauge Tool for Guitar Bass Stainless Steel Measuring Kit for Electric Bass and Acoustic Guitar by AENMIL String Action Ruler Fit for electric guitar, Bass , acoustic guitar,mandolin,banjo,etc With conversion chart of string action at 12th fret printed on one side With scale to measure string height, bridge saddle height, saddle slot depth, pickup polepiece height, fret slot depth and nut height Made of stainless steel which is stable,durable,beautiful and widely used Convenient ,pocket-sized ruler which can take to everywhere you like