The Extech MA410T is a 400 amp True RMS AC clamp meter capable of safely and efficiently measuring current without test leads. True RMS provides more accurate AC readings when measuring distorted waveforms. The integrated NCV detector enables users to quickly check for the presence of live wires before testing. Digital multimeter functions on the MA410T include: AC/DC voltage (600 volts); resistance (40 M?); capacitance (100 µF); frequency (10 kHz); temperature (-4 to 1400 degrees F/-20 to 760 degrees C); duty cycle; diode; and continuity. The MA410T also provides a 1.2-inch (30mm) jaw opening size for conductors up to 350 MCM; 4000 count backlit display; and data hold; relative mode; and auto power off functions