Klein Tools RT210 AC Electrical Outlet Wire Detection Detector GFCI Receptacle TesterProduct description Detects the most common wiring problems in standard and GFCI receptacles Works on GFI outlets and confirms operation of the ground fault protective device Conforms to UL Std 1436, Certified to CSA Std C22. 2 #160 Built to withstand a 6. 6 foot (2m) drop Operating temp: 32 degrees F to 140 degrees F (0 degrees C to 40 degrees C) Nominal Voltage: 110 125V AC at 50 60Hz in 3 wire outlet GFCI Receptacle Tester for North American AC