LART Voltage Tester, Multi-sensor safe Voltage Measuring Tool / Non Contact Electrical Test Pencil Voltage Tester pen Electrometric Detector Ac 90--1000V Non-contact test pen, totally insulated. Ballpoint will flash and beep when the the electric line is detected. Easy to tell which line is defective. More safety guarantee! Unique LED light on the pen point, it can act as a wonderful flashlight when you press the button. An essential tool in the dark environment. Safe for locating and measuring low and high amperage. Sensitivity Range 90 - 1000 VAC Absolutely essential for electrical, remodeling, and/or home improvement projects Powered By: 2 x AAA Batteries (Not included). Please note: The LED Will not flash if the battery runs out