The Faithfull Socket Polarity Tester tests sockets quickly and easily. It can be used to determine whether socket wiring is correct or incorrect. Used in conjunction with the coding table provided, the 3 combined lamps indicate the state of the socket's wiring condition. The compact and durable design is easy to operate and read. Just plug into a socket for automatic detection. Specification Socket Type UK 240V 3-Pin Nominal Voltage 240V Frequency Range 5060Hz Operating Temperature 0C to 40C Dimensions 71 x 62 x 62mm Weight approx. 63g