Klein Tools RT210 Outlet Tester, Receptacle Tester for GFCI / Standard North American AC Electrical Outlets, Detects Common Wiring Problems, Pack of 1, Factory - Amazon.com
Gardner Bender GFI-3501 Ground Fault Receptacle Tester & Circuit Analyzer, 110-125V AC, for GFCI / Standard / Extension Cords & More, 7 Visual LED Tests , Red - Circuit Testers - Amazon.com