The FLIR DM64-NIST is the right choice for professionals who install, inspect, and maintain HVAC systems. It includes microamp measurement to test flame sensors, LoZ mode to prevent ghost voltage, measures capacitance and frequency, and features a Type-K thermocouple input for temperature measurement. A flashing backlight and audible indication simplify the task of checking wiring connections and switch operation in noisy work environments; and probe-contact voltage detection helps you more precisely identify live wires. Comes with certificate traceable to NIST.