Features:
1.Suitable for string instruments such as guitar,bass,mandolin,banjo,etc.
2.Can be used to measure:Pickup polepiece height/String height /Bridge saddle height/Fret slot depth(unbound ringerboards)/Nut height/Saddle slot depth.
3. Useful conversions, from inch fractions, to inch decimals,to metric in increments
4.Made of stainless steel,never wear off,with polished rounded edges and corners to prevent scratching.
5.Pocket-sized and shape for easy and convenient storage and transport.
6.Long lasting etched printing ,the printing will not wear off from long use.
7.Easy to use whether you are doing your first guitar setup or or a professional luthier.

Specifications:
Material: Stainless Steel.
Size:9mmX51mm .
Unit: in/mm (1INCH=25.4MM)
Application: Electric guitar, acoustic guitar, bass, mandolin, banjo, etc.
Scale for string height: 0.01-0.14"/ 0.25-3.50mm
Scale for bridge saddle slot depth: 0-0.875" / 0-20mm
Scale for nuts saddles and polepieces: 0-0.75" / 0-20mm
Ruler size: 8.9 * 5.1cm / 3.5 * 2" (length * width)
Ruler weight: 19g / 0.04lbs

Package including:
1 x String action ruler
1 x Instruction paper card