UNI-T's UT139B is a True RMS Auto Range Digital Multimeter with 4000 display count and 1kHz bandwidth featuring VFC NCV Max/Min/Rel measurements.UT139B digital multimeter is newly designed to offer users better performance and higher safety rating. Total over-load protection and unique structural design make it a new type of multimeter with high performance/ price ratio and a best choice for electricians used in electrical maintenance and repairing. Suitable for high level use in education.The meter can measure AC/DC Voltage and Current variable frequency voltage (V.F.C.) resistance diode circuit on-off capacitance frequency ratio.Main features:MAX/MIN/REL modesData hold LED backlight auto power offVFC: low pass filterFull range protection (600V)True RMSNCVAuto/manual ranges selectable