Fangrui Product Details Portable Electric Socket Tester --habotest Advanced Socket Tester For Rapidly Detecting Whether The Sockets Wire Connection Is Correct Or Not. Compact Size, Light Weight And Convenient To Use. With Voltage Backlight Lcd Display For Testing Voltage. Plug Play --- Designed With Rcd/gfci Test Button, One Click To Know The Working State Of The Leakage Protector. For Protect Your Security Against The Risk Of Electric Shock. Bright Led Display --- Habotest Light Patterns Are Well Labeled On The Back Of The Device Itself. The Red Led Indicators Can Be Light Up Clearly Even In Strong Sunlight Also Be Used In The Dark, Making You Read It Fast. 6 Led Light Patterns --- Habotest With 6 Easy To Read Indicators To Indicate The State Of The Socket, Easy To Judge: Correct, Open Ground, Open Neutral, Live/neutral Reverse, Live/ground Reverse, Live/ground Reverse, Missing Ground. Wide Application - Widely Used For Electric Maintenance Testing, Office Sockets Testing, Power Strips Testing And Wall Sockets Testing