The MT222 AC High Voltage Detector is a personal sensor for detecting AC Voltage from 100V AC to 22kV AC and alert users with bright LED indication and a loud audible buzzer sound, while approaching live equipment where dangerous voltage is present. The MT222 provides electric engineering personnel, power engineering personnel, firefighting personnel and instrument equipment workers with prominent warning when approaching high voltage source. Supplied with a rubber strap and hooks, the unit can be worn on the wrist, around the arm or placed on a safety helmet. The unit uses a CR2032 battery and typical battery life is around 50 hours.