Non-Contact detection of AC Voltage from 12VAC to 600VAC Sensitivity adjustment increases or reduces sensor trigger threshold Audible and visible voltage indication Self test function Specifications Voltage Sensitivity 12V to 600VAC (50 to 500Hz) Operating Temperature/Humidity -10"C to 50"C (14 to 122"F) Battery 4 LR44 Voltage 12 to 600V AC Weight 42g (2oz) Relative humidity 80% Storage temperature -20 to 60C (4 to 140"F) Dimensions 155x28x25mm (6.3x0.75x1in) Operating altitude 7000 ft. (2000 meters)