Accurate manufacturing, accurate scale, micro error. Millimeter and inch double scale, convenient to use.32 Blade Feeler Gauge: This set of 32 feeler gauges can perform a wide variety of functions including measure fret clearance, fingerboard clearance, hardware installation and to setup proper nut slot depth. Thumbwheel allows for easy removal of individual feeler gauges for more flexibility in use. Each feeler gauge is marked with both metric and imperial measurements. Understring Radius Gauges: Use it to accurately setup your guitar bridge-saddles to matching the fingerboard radius. Features: 32 Blade Feeler Gauge: Complete 32 blade feeler gauge set for guitar setupand nut slot making. Each feeler gauge is marked with both metric and measurements. Can perform a variety of functions including measure fret clearance, fingerboard clearance, hardware installation and to setup proper nut slot depth. Thumbwheel for easy removal of individual feeler gauges. Ruler: Accurate manufacturing, accurate scale, micro error. Millimeter and inch double scale, convenient to use. You can scale such as guitar bridge-saddle height, string height, saddle slot depth, pickup polepiece height, nut height, fret slot depth(unbound fingerboards) etc. Guitar Radian Ruler: The guitar radian ruler is necessary for diy acoustic guitar. Understring Radius Gauges: Obtain accurate measurements of your instrument's fretboard radius using the bottom radius of the gauge. Then use the matching radius of this gauge to determine the proper height adjustment for the bridge-saddles. These come in the most popular fingerboard radius and make it easy to measure the radius from either above or below the strings. Specifications: Main color: silver Main material: stainless steel Understring radius gauge: 7.25", 9.5", 10", 12", 14", 15", 16", 17", 20" (all included) Feeler Gauge measurement: 0.04mm-0.88mm / 0.015in-0.035in Package size: 100 * 50 * 50mm / 3.9 * 2.0 * 2.0in Package weight: 272g / 9.6ounce Packing List: 1 * Guitar Ruler 4 * Acoustic Guitar Radian Ruler 9 * Understring Radius Gauges 1 * 32 Blade Feeler Gauge