The Extech PQ2071-NIST is a 1-/3-Phase 1000 Amp True RMS AC Power Clamp Meter. Extech's multifunctional PQ2071 Power Clamp meter operates as a True RMS Clamp Meter, Power Meter, Multimeter, and AC Voltage Detector. Featuring a CAT IV-600 Volt safety rating, the PQ2071 measures AC Current, Voltage, Frequency and Power including True Power, Apparent Power, Reactive Power and Active Power. It measures 1-Phase and balanced 3-Phase True Power (kW), Apparent Power (kVA), Reactive Power (kVAR) and Active Power (kWh), plus Power Factor and Phase Angle. The meter features a 2.16 in. (55 mm) clamp jaw opening, large dual backlit LCD display (9999 count) with bargraph, and frequency measurements to 200Hz. Users can manually store/recall up to 99 data sets. It features Data Hold, Max/Min, and Auto power off functions. It has a USB interface for connection to a PC for data logging function with included software. It includes NIST Certification.