This device is used for AC/DC voltage, continuity and phase rotation tests, for short circuit, positive and negative polarity and single lead (L2) voltage detection.UNI-T UT15B Multifunction Voltage Tester Features?Functions: ?AC/DC voltage measurements?continuity test?phase rotation test?single lead (L2) voltage detection?short circuit detection?Autoranging ?Low battery indication ?Positive and negative polarity detection?Torch