String Action Ruler Gauge Tool in/mm for Guitar Bass Mandolin Banjo

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.