"Now here’s a trusty friend all musicians and technicians need in order to keep strings at the right height. I have been using a six inch ruler exactly like this since 1971 and it always tells the truth! I keep my guitars in good set-up all the time. Measure from the top of the fret to the bottom of the string at the first fret and at the 12th fret." ~ René Martinez Stainless steel 6'' ruler. Measures 64ths and 32nds of an inch. Essential for setting up guitars. Pocket clip/slide also included (not pictured).