CLEAR LCD COLOR DISPLAY - for MESTEK electrical outlet tester is designed with a large VA reverse display color screen for easy visual indication, even in sunlight or dimly lit areas,more intuitive than other socket tester on the market, can better distinguish the data at a glance.The clear LCD Readout can show the results of wiring conditions,voltage, and the time required to trip a GFCI device, no need to look at a chart to understand results,allowing for quick and accurate troubleshooting. OUTLET TESTER WITH GFCI - The receptacle tester is designated for North American Standard 3-wire 120V electrical outlets.Test GFCI trip time in seconds to find out if the trip breaker is functioning.It can detect and identify common wiring faults, ensuring electrical safety and proper functionality of GFCI receptacles, it can be used for plug security testing in homes, factories, office, or buildings. Note: Please test the GFCI on the line with the correct wiring and circuit breaker installed. DETECT COMMON WIRING FAULTS - for MESTEK ST06 is an electrical socket tester that can detect the most common wiring faults of Wire Correct, Open Ground, Open Neutral, Open Hot, Hot/ground Reverse, Hot/neutral Reverse, and Dual Open (neutral & ground) in standard 3-wire and GFCI electrical outlets. USER-FRIENDLY PLUG TESTER - Just plug the socket tester into the standard outlet, and it will show the result on the screen within 3 seconds. The auto-hold function is convenient for hard-to-reach outlets, bright LED lights illuminate green and red for easy visual indicators. Plug Type:US Plug, it applies to Canada, India, Mexico, Thailand, Taiwan, the United States, the Philippines and so on. Voltage:AC110V Colour:Orange Material:Plastic Package Contents: 1 * Outlet Socket Checker