Voltage Tester Pen - TOOGOO(R)Digital Voltage Tester Pen Detector Volt Tester AC/ DC 12-250 V with LED Display Measuring range: 12 220V 5 phases: 12V, 36V, 55V, 110V, 220V The product can be DC/ AC 12 220V checked directly. Battery is unnecessary. Fast Track and testing.