The IDEAL Electrical 61557 Voltage and Continuity Tester measures AC and DC voltage, Low Impedance AC Voltage (Lo Z) (to reduce the possibility of false readings due to ghost voltages), and continuity, via test-leads. It detects the presence of voltage between 90V to 600V AC via a non-contact sensor in the top center of the meter and can perform a GFCI trip test via the probes and test button. 61-557 has an LCD display that can be backlit, and a built-in flashlight that can be illuminated when working in poor or zero lighting conditions. The unit uses an illuminated red LED in the center of meter and audible tones to notify when voltage is above 36V AC / 50V DC , when continuity is detected and when the NCV senses voltage within its set range. The back of the meter has built-in two position dual probe holder; the lower position allows for probe storage, the higher position allows for and testing or measurement holding the meter and secured probe in one hand and the probe in the other hand, or for both probes to be secured in the tip while conducting outlet testing. 61-557 has a hanging strap mount (compatible with all other IDEAL Electrical meters with this feature) that allows for a hanging strap (not included) to be attached to the meter so it can be hung from a nail, screw or magnetic surface. A Pro industrial grade over molding design makes this tester easy to grip and capable of sustaining a drop from 6.5 ft (2 m). This meter features a Self-Test at each Power ON, Automatic AC/DC voltage and DC polarity detection, a low battery indication, an Auto Power Off function, and comes with 3 1.5V AAA Batteries.