The Extech DVA30 is the only two-in-one current/voltage detector designed for electrical testing. It detects AC voltage from 12 Volts to 600 V and AC current from 200 mA (0.2 in. distance) to large current flows, up to 1000 Amps, from a distance. Sensitivity adjustments increase or reduce sensor trigger threshold. Audible and visual indicators show the presence of current or voltage. The DVA30 can be used to trace concealed wires in walls and floors, identify hot wires, trace current flow behind walls, in conduits, through concrete, or underground. The sensitivity is high enough to trip on low voltage HVAC or similar signal levels. Complete with four LR44 button batteries and pocket clip.