Triplett Sniff-It 2 9601 Pocket-sized Non-Contact AC Voltage Detector measures AC voltage from 5V to 600V without direct contact. The Triplett Sniff-It 2 features a side-knob to adjust sensitivity, visual and audible voltage indication, a small design that easily fits into pockets, and the ability to work on live outlets, wires, and ringing telephones lines. The Triplett Sniff-It 2 9601 Pocket-sized Non-Contact AC Voltage Detector is a truly versatile non-contact voltage detector with an impressive voltage range from 5V to 600V and compact design.