granite square ruler

On inspection of verticality and parallelism as well as absolure 90°measuring
Granite square rulers suitable for the detection of verticality, plane accuracy of the standard GB6092-85, the vertical standard GB6092-85. To reduce weight and to facilitate the processing and reduction bores.
Granite square rulers is mainly used for the workpiece flatness, perpendicularity, straightness measurement
Rock by long-term natural aging, organizational structure, uniform, linear expansion coefficient is very small, the internal stress completely disappeared, no deformation, so the accuracy is high.
granite square ruler