Features: With scale for string height, for ridge saddle slot depth and for nuts saddles and polepieces. With conversion chart of string action at 12th fret printed on one side. Long lasting etched printing, the printing will not wear off from long use. Suitable for string instruments such as guitar, bass, mandolin, banjo, etc. Specifications: Material: Stainless steel Unit: mm / in Scale for string height: 0.01-0.14in / 0.25-3.50mm Scale for bridge saddle slot depth: 0-0.875in / 0-20mm Scale for nuts saddles and polepieces: 0-0.75in / 0-20mm Ruler size: 8.9 * 5.1cm / 3.5 * 2in (length * width) Ruler weight: 21g / 0.7oz