[Professional Guitar Tools] Guitar luthier tool set includes: 32 Blades Steel Feeler Gauge Dual, 9 Understring Radius Gauge, 1 String Action Gauge Ruler, 2 Fingerboard Guards and 1 Grinding Stone in a velvet bag | [32 Blades Feeler Gauge] Steel Feeler Gauge measuring range: 0.0015 inch/ 0.04 mm to 0.035 inch/ 0.88 mm, light oil covered to prevent rust and stick, thumb screw is easy to use for blade removal and protection | [9 Understring Radius Gauge] Stainless steel material, set of 9 including: 7.25", 9.5", 10", 12", 14", 15", 16", 17" and 20" radius, luthier tools for guitar and bass setup | [High Quality] Made of stainless steel with rounded off edge, anti rust, prevent scratch or cutting, durable and long service life | [Wide Usage] Suitable for measure all kinds of electric guitar, electric bass, acoustic guitar, acoustic guitar, electric box guitar fretboard measured in radians, radians to adjust the strings piano code