Features: *Brand new and high quality. *The polarity detection of the three-hole power socket wiring. *The protection function detection of the leakage switch. *It can quickly and accurately detect the wiring. *Widely USed in fire, laboratory, factory, family. *The high-definition display can see the screen value clearly in the dark environment. Specifications: Part Name:Socket Tester Material:Plastic Size:About 8*7.5*7.5CM Color:Black Zero-live voltage measure(L-N)：30-250V/(50-60HZ) Zero-earth voltage measure(N-E)：0.1-10V/(50-60HZ) Working environment：Temp0℃-40℃/humidity(20%-70%) Storage environment：Temp10℃-50℃/humidity(20%-80%) RCD Current：>30mA RCD Working voltage：220V±20V Battery：AAA 2 battery(not included) Package Content: 1 x Socket Tester Tips: 1.The normal voltage range of zero fire line is plus or minus 10%of the local standard voltage.If it is too high or too low,it may be because the circuit load is too high or the power supply is too low/too high. 2.The normal voltage of zero-earth wire is less than 2V,if too high maybe it is because there is current leakage,or the three phase-sequence is out of balance or there is signal interference in the circuit. 3.Please turn off all electrical appliances before USing this function,and do so with permission to ensure that the power outage will not cause any harm. Note: 1. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2. Please allow slight manual measurement deviation for the data. Made of high quality material, durable and practical to use. Perfect functions,give you a wonderful experience. Every customer can enjoy 30 days refund or replacement for Damaged/Quality Issues. If you have any questions, please feel free to contact us, we will solve it for you. Socket Tester Test Outlet Voltage Tester Plug Ground Zero Line Smart Detector