The Triplett Sniff-It 3 is a high performance AC Voltage detector with adjustable sensitivity that has a wide measurement range of 25 to 1000ACV, Dual Color Tip to indicate low/high voltage, built-in flashlight and durable overmold. The high sensitivity allows it to detect low voltage AC wiring commonly found in doorbell circuits, thermostats, control circuits, and video surveillance camera power. The Sniff-It 3 is designed for industrial applications with its impact and drop resistance in a sleek ergonomic design, and the easy to use thumb wheel helps dial-in detection range. Includes (2) AAA batteries. CAT III safety rating.