Check the diameter of holes with the pull of a trigger. These Starrett sets have everything you need for one-handed measurements—a pistol-grip gauge, heads for varying diameters, and setting rings. Thanks to its pistol grip, you can reach the gauge into awkward spots, such as those overhead. The pistol grip also gives you precise control using just your fingertips instead of your whole hand. Unlike dial bore gauges, you can measure right away, no baseline measurement required. You can even set upper and lower tolerances for quick go/no-go tests. The LCD display has lights and arrows to show if the hole falls within your set tolerance. Rotate the display to read results at the angle you need.

Since the gauge has three contact points, it’s more accurate than a typical bore gauge with two contact points. The probe centers itself, so it’s easier to detect issues with roundness, a common check in quality control tests. To stay accurate, the gauge has alarms to warn you about problems that could skew readings, such as a low battery, a contaminated probe, and test setting errors. Use the included setting rings to calibrate your gauge.

With a zero-set button, you can start measuring at any point. Zero-position memory, also known as absolute (ABS) positioning, retains the measuring position when the gauge is off. Connect the gauge to your computer, smartphone, or other device via Bluetooth or the SPC data output to monitor and analyze data in real time.