... Voltage Detector Sensor Tester Pen 90-1000V Features:Electric Socket Wall AC Power Outlet Voltage Detector Sensor Tester Pen 90-1000VThe ... , or supply cord. When the tip glows red and the unit beeps, you know there is voltage present. Electricians, maintenance, ... industry uses Ideal design for testing power cables, circuit breakers, wall sockets, junction boxes, fuses, etc Just press the button, white ...