The Triplett Model CM400 True RMS Clampmeter can measure AC current up to 400A without breaking the circuit by clamping around a single conductor. This saves time and the circuit will not be damaged. True RMS provides better accuracy when measuring non-sinusoidal or noisy waveforms. Additional measurements include Resistance, Capacitance, Frequency, Temperature, Diode Test, and Continuity. Measurements can read on the 4000 count backlit LCD. It has an Inrush current function that captures the instantaneous surge (inrush) current when power equipment is turned on. Features include: Peak voltage capture with min/max, NCV Detector with LED, Relative/DC zero function, Auto power off, and a built-in flashlight. Data Hold freezes the display for easy viewing. CAT III-600V safety category. Includes 3 AAA batteries, test leads, Type K thermocouple probe, and carrying case.