Check readings at a glance—the display on these indicators changes color when a measurement is outside your tolerance. The LCD screen changes from green to yellow when measurements are almost out of tolerance, then to red once they fall out of bounds. These indicators come with a calibration certificate traceable to NIST that states they’ve passed a test for accuracy. To measure objects, they have a spring-loaded plunger that retracts and extends.

These indicators can measure TIR (total indicated runout), which determines the range of high and low spots on round parts. All have zero-position memory, also known as absolute (ABS) positioning, which retains the measuring position when the indicator is off. A zero-set button lets you start measuring at any point. Since they have an SPC data output, you can connect them to your computer or data processor.