Test for size deviations across a range of hole diameters. These sets include 3 gauges and over 25 anvils marked by size for quick changes. Use them to test engine cylinders, machine components, and other parts for issues with roundness and taper. They have a two-point contact system, which is the most common design for bore gauges. For a long service life, the jeweled bearings in each dial head resist wear, and a plastic cover protects the head from scratches and drops.

Check size deviations by first setting the desired measurement with a ring gauge, bore gauge calibrator, micrometer, or caliper. The dial will display the magnitude of variation from the set measurement.