Review on 🔌 Sperry Instruments VD7504GFI: DualCheck Non-Contact Voltage Detector + GFCI Outlet Circuit Analyzer with Visual & Audible Indicators, 50-1000V AC, 250 lb. Crush Rating by David Gagnon

Works great when the Li-Ion battery (included) is properly installed. There is no polarity indicator so I figured polarity might not matter. It did not work. I was going to send it to Redbox for a refund but figured I'd flip the battery over to check. It did. The illustration shows the correct polarity - (+) to the live tester probe. Other than that (one star deducted) it's very light and ergonomic, easy to use and I love the fact that I have the tester on the opposite socket. the end.