Fluke 1AC-A1-II Volt-Alert AC Non-Contact Voltage Tester:Simply touch the tip to a terminal strip, outlet or cord. When the tip glows red, and the unit beeps, you know there's voltage in the line. Electricians, maintenance, service, safety personnel can quickly test for energized circuits and defective grounds on the factory floor, in the shop. Continually tests its battery and its circuit integrity with a periodic double flash visual indication using Fluke Voltbeat technology. It comes with a two-year warranty. It detects line voltage from 90VAC - 600VAC (1AC-AI-II).