Feature: 1. The guard system can be tested to ensure the safety of household appliances and protect your safety, to protect you from the risk of electric shock. 2. Used to detect whether the null line, live wire, and the ground wire are connected correctly, and indicate the wire that lack of a clear light pattern. 3. It is widely used in power maintenance test, office socket test, power strip test and power socket test, in schools, laboratories, factories and other social fields. 4. With 7 easy‑to‑read indicator lights to indicate the status of the socket, easy to judge, can improve your work efficiency. 5. There are bright LED indicators and 3 test indicators on the display, which is very convenient for reading. Specification: Item Type: Socket Tester Material: Plastic Color: As Pictures Shown Model: HT106D RCD Test: >30mA Display: LCD Socket Wiring Detection: The Wiring is Correct: the Left and Middle Indicator Lights are on Missing Ground Wire: the Indicator on the left is on Missing Null Line: the Middle Indicator Light is on Missing Live Wire: All Lights are Off The live wire and the ground wire are reversely connected, the middle and right indicator lights are on The live wire and the null line are reversely connected, the left and right indicator lights are on The ground wire is missing or may be the ground wire connected to the neutral wire,3 indicator are all on. Package List: 1 x Socket Tester1 x Manual