A friction thumb roller allows for precision in four different measurements, outside, inside, depth and step. With an easy to read digital screen which show units in both inches and metric reading 0.001"/0.1mm for easy conversions. With an adjustable zero it is also easy to measure hard to reach objects and allows for better utility. Fiberglass reinforcements allow this tool to be taken wherever the job is without fear of breakage, ideal for all those rough jobs. This General Alvin Caliper,6In,Digital model is suited best for right hand dominant people so the screen will face you while taking measurements.