Strong adsorption to improve efficiency The strong designs of the head can adsorb screws and small metal parts to improve work efficiency Identify the live wires : the live wires on , the 0 wire is off Designed for electricians , maintenance personnel , and home users who need to and measure circuits This LED high brightness buzzer sensing voltage tester pen features a bright LED light and a buzzer , making it easy to detect voltage The LED light provides long lasting , while the buzzer alerts users to potential hazards, Manufacturer: Watreketal