Manual ranging DMM with NCV detector and battery test function The Extech EX310-NIST is a compact manual ranging multi meter which features an extra-large 2000 count display and built-in non-contact AC voltage detector (NCV). AC/DC Voltage & Current, Resistance, Diode/Continuity measurements. Includes battery test function (1.5 Volt and 9 Volt). Rubber holster protects the meter. UL listed Cat III – 600 Volt safety rating. With NIST Calibration.